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The following are examples of
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
for different
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s. __TOC__


Overview


Detailed list

To help compare different orders of magnitude, the following list describes various lengths between 1.6 \times 10^ metres and 10^metres.


Subatomic scale


Atomic to cellular scale


Cellular to human scale


Human to astronomical scale


Astronomical scale


Less than 1 zeptometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to . To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s shorter than 10−21 m (1 zm). *1.6 × 10−5 quectometres (1.6 × 10−35 metres) – the Planck length (Measures of distance shorter than this do not make physical sense, according to current theories of
physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which relat ...
.) *1 qm – 1 quectometre, the smallest named subdivision of the metre in the
SI base unit The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all ...
of length, one nonillionth of a metre *1 rm – 1 rontometre, a subdivision of the metre in the
SI base unit The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all ...
of length, one octillionth of a metre *10 rm – the length of one side of a square whose area is one
shed A shed is typically a simple, single-story roofed structure that is used for hobby, hobbies, or as a workshop in a back garden or on an allotment (gardening), allotment. Sheds vary considerably in their size and complexity of construction, fr ...
, a unit of target cross section used in
nuclear physics Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the ...
*2 ym – the effective cross-section radius of 1 
MeV In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacuum. ...
neutrino A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is ...
s as measured by
Clyde Cowan Clyde Lorrain Cowan Jr (December 6, 1919 – May 24, 1974) was an American physicist, the co-discoverer of the neutrino along with Frederick Reines. The discovery was made in 1956 in the neutrino experiment. Frederick Reines received the Nobel Pr ...
and
Frederick Reines Frederick Reines ( ; March 16, 1918 – August 26, 1998) was an American physicist. He was awarded the 1995 Nobel Prize in Physics for his co-detection of the neutrino with Clyde Cowan in the neutrino experiment. He may be the only scientist ...


1 zeptometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to . To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−21 m and 10−20 m (1 zm and 10 zm). *2 zm – the upper bound for the width of a
cosmic string Cosmic strings are hypothetical 1-dimensional topological defects which may have formed during a symmetry-breaking phase transition in the early universe when the topology of the vacuum manifold associated to this symmetry breaking was not simpl ...
in string theory. *2 zm – radius of effective
cross section Cross section may refer to: * Cross section (geometry) ** Cross-sectional views in architecture & engineering 3D *Cross section (geology) * Cross section (electronics) * Radar cross section, measure of detectability * Cross section (physics) **Abs ...
for a 20
GeV GEV may refer to: * ''G.E.V.'' (board game), a tabletop game by Steve Jackson Games * Ashe County Airport, in North Carolina, United States * Gällivare Lapland Airport, in Sweden * Generalized extreme value distribution * Gev Sella, Israeli-Sou ...
neutrino A neutrino ( ; denoted by the Greek letter ) is a fermion (an elementary particle with spin of ) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is ...
scattering off a
nucleon In physics and chemistry, a nucleon is either a proton or a neutron, considered in its role as a component of an atomic nucleus. The number of nucleons in a nucleus defines the atom's mass number (nucleon number). Until the 1960s, nucleons were ...
*7 zm – radius of effective cross section for a
250 __NOTOC__ Year 250 ( CCL) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Traianus and Gratus (or, less frequently, year 1003 ''Ab u ...
GeV neutrino scattering off a nucleon


10 zeptometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−20 m and 10−19 m (10 zm and 100 zm).


100 zeptometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−19 m and 10−18 m (100 zm and 1 am). *177 zm –
de Broglie wavelength Matter waves are a central part of the theory of quantum mechanics, being an example of wave–particle duality. All matter exhibits wave-like behavior. For example, a beam of electrons can be diffracted just like a beam of light or a water wave ...
of
protons A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...
at the
Large Hadron Collider The Large Hadron Collider (LHC) is the world's largest and highest-energy particle collider. It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and hundre ...
(7 TeV as of 2010)


1 attometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to . To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−18 m and 10−17 m (1 am and 10 am). *1 am – sensitivity of the
LIGO The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Two large o ...
detector for
gravitational wave Gravitational waves are waves of the intensity of gravity generated by the accelerated masses of an orbital binary system that propagate as waves outward from their source at the speed of light. They were first proposed by Oliver Heaviside in 1 ...
s *1 am – upper limit for the size of
quark A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly o ...
s and
electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no kno ...
s


10 attometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−17 m and 10−16 m (10 am and 100 am). *10 am – range of the weak force


100 attometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−16 m and 10−15 m (100 am and 1 fm). *100 am – all lengths shorter than this distance are not confirmed in terms of size *850 am – approximate proton radius


1 femtometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to . In
particle physics Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) and b ...
, this unit is more commonly called a , also with abbreviation "fm". To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−15
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s and 10−14 metres (1 femtometre and 10 fm). *1 fm – diameter of a
neutron The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons behav ...
, approximate range-limit of the
color force Color Force is an American independent film and television production company founded in 2007 by producer and film executive Nina Jacobson after her 2006 termination as president of Disney's Buena Vista Motion Pictures Group. Its films incl ...
carried between
quark A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly o ...
s by
gluon A gluon ( ) is an elementary particle that acts as the exchange particle (or gauge boson) for the strong force between quarks. It is analogous to the exchange of photons in the electromagnetic force between two charged particles. Gluons bind q ...
s *1.5 fm – diameter of the
scattering cross section In physics, the cross section is a measure of the probability that a specific process will take place when some kind of radiant excitation (e.g. a particle beam, sound wave, light, or an X-ray) intersects a localized phenomenon (e.g. a particle o ...
of an 11
MeV In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacuum. ...
proton A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...
with a target proton *1.75 fm – the effective charge diameter of a
proton A proton is a stable subatomic particle, symbol , H+, or 1H+ with a positive electric charge of +1 ''e'' elementary charge. Its mass is slightly less than that of a neutron and 1,836 times the mass of an electron (the proton–electron mass ...
*2.81794 fm –
classical electron radius The classical electron radius is a combination of fundamental physical quantities that define a length scale for problems involving an electron interacting with electromagnetic radiation. It links the classical electrostatic self-interaction energ ...
*3 fm – approximate range-limit of the nuclear binding force mediated by
meson In particle physics, a meson ( or ) is a type of hadronic subatomic particle composed of an equal number of quarks and antiquarks, usually one of each, bound together by the strong interaction. Because mesons are composed of quark subparticles, ...
s *7 fm – the radius of the effective scattering cross section for a gold nucleus scattering a 6
MeV In physics, an electronvolt (symbol eV, also written electron-volt and electron volt) is the measure of an amount of kinetic energy gained by a single electron accelerating from rest through an electric potential difference of one volt in vacuum. ...
alpha particle Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus. They are generally produced in the process of alpha decay, but may also be produce ...
over 140 degrees


10 femtometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−14 m and 10−13 m (10 fm and 100 fm). *1.75 to 15 fm – Diameter range of the atomic nucleus


100 femtometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−13 m and 10−12 m (100 fm and 1 pm). *570 fm – typical distance from the atomic nucleus of the two innermost electrons (electrons in the ''1s'' shell) in the
uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weakly ...
atom, the heaviest naturally-occurring atom


1 picometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−12 and 10−11 m (1 pm and 10 pm). *1 pm – distance between
atomic nuclei The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment. After the discovery of the neutron i ...
in a
white dwarf A white dwarf is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to the Sun's, while its volume is comparable to the Earth's. A white dwarf's faint luminosity comes f ...
*1 pm – reference value of particle displacement in acoustics *2.4 pm – The
Compton wavelength The Compton wavelength is a quantum mechanical property of a particle. The Compton wavelength of a particle is equal to the wavelength of a photon whose energy is the same as the rest energy of that particle (see mass–energy equivalence). It wa ...
of an
electron The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no kno ...
*5 pm – shorter
X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10  picometers to 10 nanometers, corresponding to frequencies in the range 30  ...
wavelengths (approx.)


10 picometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−11 and 10−10 m (10 pm and 100 pm). *25 pm – approximate radius of a helium atom, the smallest neutral atom *50 pm – radius of a hydrogen atom *50 pm –
bohr radius The Bohr radius (''a''0) is a physical constant, approximately equal to the most probable distance between the nucleus and the electron in a hydrogen atom in its ground state. It is named after Niels Bohr, due to its role in the Bohr model of an ...
: approximate radius of a hydrogen atom *~50 pm – best resolution of a high-resolution transmission electron microscope *60 pm – radius of a carbon atom *93 pm – length of a
diatomic carbon Diatomic carbon (systematically named dicarbon and 1λ2,2λ2-ethene), is a green, gaseous inorganic chemical with the chemical formula C=C (also written 2or C2). It is kinetically unstable at ambient temperature and pressure, being removed throug ...
molecule *96 pm – H–O bond length in a
water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...
molecule


100 picometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−10 and 10−9 m (100 pm and 1 nm; 1  Å and 10 Å). *100 pm – 1
ångström The angstromEntry "angstrom" in the Oxford online dictionary. Retrieved on 2019-03-02 from https://en.oxforddictionaries.com/definition/angstrom.Entry "angstrom" in the Merriam-Webster online dictionary. Retrieved on 2019-03-02 from https://www.m ...
*100 pm –
covalent radius The covalent radius, ''r''cov, is a measure of the size of an atom that forms part of one covalent bond. It is usually measured either in picometres (pm) or angstroms (Å), with 1 Å = 100 pm. In principle, the sum of the two cova ...
of
sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...
atom *120 pm –
van der Waals radius The van der Waals radius, ''r'', of an atom is the radius of an imaginary hard sphere representing the distance of closest approach for another atom. It is named after Johannes Diderik van der Waals, winner of the 1910 Nobel Prize in Physics, ...
of a neutral
hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxi ...
atom *120 pm – radius of a gold atom *126 pm – covalent radius of
ruthenium Ruthenium is a chemical element with the symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals ...
atom *135 pm – covalent radius of
technetium Technetium is a chemical element with the Symbol (chemistry), symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive. All available technetium is produced as a synthetic element. Naturally occurring techneti ...
atom *150 pm – Length of a typical
covalent bond A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atom ...
( C–C) *153 pm – covalent radius of
silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical co ...
atom *155 pm – covalent radius of
zirconium Zirconium is a chemical element with the symbol Zr and atomic number 40. The name ''zirconium'' is taken from the name of the mineral zircon, the most important source of zirconium. The word is related to Persian '' zargun'' (zircon; ''zar-gun'', ...
atom *175 pm – covalent radius of
thulium Thulium is a chemical element with the symbol Tm and atomic number 69. It is the thirteenth and third-last element in the lanthanide series. Like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other c ...
atom *200 pm – highest resolution of a typical
electron microscope An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a h ...
*225 pm – covalent radius of
caesium Caesium ( IUPAC spelling) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only five elemental metals that a ...
atom *280 pm – Average size of the
water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...
molecule *298 pm – radius of a
caesium Caesium ( IUPAC spelling) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only five elemental metals that a ...
atom, calculated to be the largest atomic radius (except possibly francium) *340 pm – thickness of single layer
graphene Graphene () is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice nanostructure.
*356.68 pm – width of
diamond Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, ...
unit cell In geometry, biology, mineralogy and solid state physics, a unit cell is a repeating unit formed by the vectors spanning the points of a lattice. Despite its suggestive name, the unit cell (unlike a unit vector, for example) does not necessaril ...
*403 pm – width of
lithium fluoride Lithium fluoride is an inorganic compound with the chemical formula LiF. It is a colorless solid, that transitions to white with decreasing crystal size. Although odorless, lithium fluoride has a bitter-saline taste. Its structure is analogous to ...
unit cell *500 pm – Width of protein α helix *543 pm – silicon lattice spacing *560 pm – width of sodium chloride unit cell *700 pm – width of
glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...
molecule *700 pm – diameter of a
buckyball Buckminsterfullerene is a type of fullerene with the formula C60. It has a cage-like fused-ring structure (truncated icosahedron) made of twenty hexagons and twelve pentagons, and resembles a soccer ball. Each of its 60 carbon atoms is bonded t ...
*780 pm – mean width of
quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical fo ...
unit cell *820 pm – mean width of
ice Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaq ...
unit cell *900 pm – mean width of
coesite Coesite is a form ( polymorph) of silicon dioxide Si O2 that is formed when very high pressure (2–3 gigapascals), and moderately high temperature (), are applied to quartz. Coesite was first synthesized by Loring Coes Jr., a chemist at the ...
unit cell


1 nanometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−9 and 10−8 m (1 nm and 10 nm). *1 nm – diameter of a
carbon nanotube A scanning tunneling microscopy image of a single-walled carbon nanotube Rotating single-walled zigzag carbon nanotube A carbon nanotube (CNT) is a tube made of carbon with diameters typically measured in nanometers. ''Single-wall carbon nan ...
*1 nm – roughly the length of a sucrose molecule, calculated by
Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...
*2.3 nm – length of a
phospholipid Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typ ...
*2.3 nm – smallest
gate A gate or gateway is a point of entry to or from a space enclosed by walls. The word derived from old Norse "gat" meaning road or path; But other terms include '' yett and port''. The concept originally referred to the gap or hole in the wall ...
oxide thickness in
microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
s *3 nm – width of a DNA helix *3 nm – flying height of the
head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may not ...
of a
hard disk A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magneti ...
*3 nm – , the average half-pitch of a memory cell expected to be manufactured circa 2022 *3.4 nm – length of a DNA turn (10 bp) *3.8 nm – size of an
albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All the proteins of the albumin family are water-soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Albumins ...
molecule *5 nm – size of the gate length of a 16 nm processor *5 nm – , the average half-pitch of a memory cell manufactured circa 2019–2020 *6 nm – length of a
phospholipid Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids typ ...
bilayer *6–10 nm – thickness of cell membrane *6.8 nm – width of a
haemoglobin Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocyt ...
molecule *7 nm – diameter of
actin filaments Microfilaments, also called actin filaments, are protein filaments in the cytoplasm of eukaryotic cells that form part of the cytoskeleton. They are primarily composed of polymers of actin, but are modified by and interact with numerous other p ...
*7 nm – the average half-pitch of a memory cell manufactured circa 2018 *10 nm – Thickness of
cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering me ...
in
Gram The gram (originally gramme; SI unit symbol g) is a unit of mass in the International System of Units (SI) equal to one one thousandth of a kilogram. Originally defined as of 1795 as "the absolute weight of a volume of pure water equal to th ...
-negative bacteria


10 nanometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−8 and 10−7 m (10 nm and 100 nm). *10 nm – the average length of a
nanowire A nanowire is a nanostructure in the form of a wire with the diameter of the order of a nanometre (10−9 metres). More generally, nanowires can be defined as structures that have a thickness or diameter constrained to tens of nanometers or less ...
*10 nm – lower size of tobacco smokeAnnis, Patty J. October 1991.
Kansas State University Kansas State University (KSU, Kansas State, or K-State) is a public land-grant research university with its main campus in Manhattan, Kansas, United States. It was opened as the state's land-grant college in 1863 and was the first public instit ...
. ''Fine Particle POLLUTION''. Figure 1. (tobacco smoke: 10 to ; virus particles: 3 to 50 nm; bacteria: 30 to ; cooking oil smoke: 30 to ; wood smoke: 7 to )
*10 nm – the average half-pitch of a memory cell manufactured circa 2016 2017 *13 nm – the length of the wavelength that is used for
EUV lithography Extreme ultraviolet lithography (also known as EUV or EUVL) is an optical lithography technology used in steppers, machines that make integrated circuits (ICs) for computers and other electronic devices. It uses a range of extreme ultraviolet (EU ...
*14 nm – Length of a
porcine circovirus Porcine circovirus (PCV) is a group of four single-stranded DNA viruses that are non-enveloped with an unsegmented circular genome. They are members of the genus '' Circovirus'' that can infect pigs. The viral capsid is icosahedral and approxim ...
*14 nm – the average half-pitch of a memory cell manufactured circa 2013 *15 nm – Length of an antibody *18 nm – diameter of
tobacco mosaic virus ''Tobacco mosaic virus'' (TMV) is a positive-sense single-stranded RNA virus species in the genus '' Tobamovirus'' that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes character ...
*20 nm – Length of a
nanobe A nanobe () is a tiny filamental structure first found in some rocks and sediments. Some scientists hypothesize that nanobes are the smallest form of life, 1/10 the size of the smallest known bacteria. No conclusive evidence exists that thes ...
, could be one of the smallest forms of life *20–80 nm – thickness of
cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering me ...
in
Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive ba ...
*20 nm – thickness of bacterial
flagellum A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have fro ...
*22 nm – the average half-pitch of a memory cell manufactured circa 2011–2012 *22 nm – Smallest feature size of production
microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
s in September 2009 *25 nm – diameter of a
microtubule Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27  nm and have an inner diameter between 11 an ...
*30 nm – lower size of cooking oil smoke *32 nm – the average half-pitch of a memory cell manufactured circa 2009–2010 *40 nm – extreme
ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30  PHz) to 400 nm (750  THz), shorter than that of visible light, but longer than X-rays. UV radiatio ...
wavelength *45 nm – the average half-pitch of a memory cell manufactured circa 2007–2008 *50 nm – upper size for airborne
virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's ...
particles *50 nm –
flying height The flying height or floating height or head gap is the distance between the disk read/write head on a hard disk drive and the platter. The first commercial hard-disk drive, the IBM 305 RAMAC, used forced air to maintain a 0.002 inch (51&nbs ...
of the
head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may not ...
of a
hard disk A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magneti ...
*65 nm – the average half-pitch of a memory cell manufactured circa 2005–2006 *58 nm – height of a
T7 bacteriophage Bacteriophage T7 (or the T7 phage) is a bacteriophage, a virus that infects bacteria. It infects most strains of ''Escherichia coli'' and relies on these hosts to propagate. Bacteriophage T7 has a lytic life cycle, meaning that it destroys the ...
*90 nm – Human immunodeficiency virus (HIV) (generally,
virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's ...
es range in size from 20 nm to 450 nm) *90 nm – the average half-pitch of a memory cell manufactured circa 2002–2003 *100 nm – Length of a
mesoporous silica Mesoporous silica is a form of silica that is characterised by its mesoporous structure, that is, having pores that range from 2 nm to 50 nm in diameter. According to IUPAC's terminology, mesoporosity sits between microporous (50  ...
nanoparticle


100 nanometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−7 and 10−6 m (100 nm and 1  μm). *100 nm – greatest particle size that can fit through a
surgical mask A surgical mask, also known by other names such as a medical face mask or procedure mask, is a personal protective equipment used by healthcare professionals that serves as a mechanical barrier that interferes with direct airflow in and out of re ...
*100 nm – 90% of particles in wood
smoke Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-produ ...
are smaller than this. *120 nm – greatest particle size that can fit through a
ULPA ULPA is an acronym for "Ultra-low Penetration Air (filter)". An ULPA filter can remove from the air at least 99.999% of dust, pollen, mold, bacteria and any airborne particles with a minimum particle penetration size of 120 nanometres (0.12  � ...
filter *120 nm – diameter of a
human immunodeficiency virus The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune ...
(HIV) *120 nm – approximate diameter of
SARS-CoV-2 Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a strain of coronavirus that causes COVID-19 (coronavirus disease 2019), the respiratory illness responsible for the ongoing COVID-19 pandemic. The virus previously had a ...
*125 nm – standard depth of pits on compact discs (width: 500 nm, length: 850 nm to 3.5 μm) *180 nm – typical length of the
rabies virus Rabies virus, scientific name ''Rabies lyssavirus'', is a neurotropic virus that causes rabies in humans and animals. Rabies transmission can occur through the saliva of animals and less commonly through contact with human saliva. ''Rabies lyss ...
*200 nm – typical size of a ''
Mycoplasma ''Mycoplasma'' is a genus of bacteria that, like the other members of the class '' Mollicutes'', lack a cell wall around their cell membranes. Peptidoglycan ( murein) is absent. This characteristic makes them naturally resistant to antibioti ...
'' bacterium, among the smallest bacteria *300–400 nm – near
ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30  PHz) to 400 nm (750  THz), shorter than that of visible light, but longer than X-rays. UV radiatio ...
wavelength *300 nm – greatest particle size that can fit through a
HEPA HEPA (, high-efficiency particulate air) filter, also known as high-efficiency particulate absorbing filter and high-efficiency particulate arrestance filter, is an efficiency standard of air filters. Filters meeting the HEPA standard must s ...
(high efficiency particulate air) filter (N100 removes up to 99.97% at 0.3 micrometres, N95 removes up to 95% at 0.3 micrometres) *400–420 nm – wavelength of violet light (see
Color Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associa ...
and
Visible spectrum The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called ''visible light'' or simply light. A typical human eye will respond to wavele ...
) *420–440 nm – wavelength of
indigo Indigo is a deep color close to the color wheel blue (a primary color in the RGB color space), as well as to some variants of ultramarine, based on the ancient dye of the same name. The word "indigo" comes from the Latin word ''indicum'', m ...
light *440–500 nm – wavelength of
blue Blue is one of the three primary colours in the RYB colour model (traditional colour theory), as well as in the RGB (additive) colour model. It lies between violet and cyan on the spectrum of visible light. The eye perceives blue when ob ...
light *500–520 nm – wavelength of cyan light *520–565 nm – wavelength of
green Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a combin ...
light *565–590 nm – wavelength of
yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the RG ...
light *590–625 nm – wavelength of
orange Orange most often refers to: *Orange (fruit), the fruit of the tree species '' Citrus'' × ''sinensis'' ** Orange blossom, its fragrant flower *Orange (colour), from the color of an orange, occurs between red and yellow in the visible spectrum * ...
light *625–700 nm – wavelength of
red Red is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nanometres. It is a primary color in the RGB color model and a secondary ...
light *700–1.4 μm – wavelength of
near-infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
radiation


1 micrometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists some items with lengths between 10−6 and 10−5 m (between 1 and 10
micrometre The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer ( American spelling), also commonly known as a micron, is a unit of length in the International System of Uni ...
s, or μm). *~0.7–300 μm – wavelength of
infrared radiation Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
*1 μm – the side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 10−12 m2 *1 μm – edge of cube of volume 10−18 m3 (1 fL) *1–10 μm – diameter of a typical
bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
*1 μm – length of a
lysosome A lysosome () is a membrane-bound organelle found in many animal cells. They are spherical vesicles that contain hydrolytic enzymes that can break down many kinds of biomolecules. A lysosome has a specific composition, of both its membrane p ...
*1–2 μm –
anthrax Anthrax is an infection caused by the bacterium '' Bacillus anthracis''. It can occur in four forms: skin, lungs, intestinal, and injection. Symptom onset occurs between one day and more than two months after the infection is contracted. The s ...
spore *2 μm – length of an average
E. coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Esche ...
bacteria *3–4 μm – size of a typical
yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...
cell *5 μm – length of a typical human
spermatozoon A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. (A zygote is a single cell, with a complete set of chromosomes, ...
's head *6 μm – thickness of the tape in a 120-minute (C120)
compact cassette The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Otten ...
*7 μm – diameter of the
nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers to: *Atomic nucleus, the very dense central region of an atom *Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA Nucle ...
of a typical eukaryotic
cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery w ...
*about 7 μm – diameter of human
red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...
s *3–8 μm – width of strand of spider web silk *5–10 μm – width of a
chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in ...
*8–11 μm – size of a ground-level fog or mist dropletBut not cloud or high-level fog droplets; droplet size increases with altitude. For a contradictory study indicating larger drop sizes even in ground fog, see


10 micrometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−5 m and 10−4 m (10 μm and 100 μm). *10 μm – width of cotton fibre *10 μm – tolerance of a
Lego Lego ( , ; stylized as LEGO) is a line of plastic construction toys that are manufactured by The Lego Group, a privately held company based in Billund, Denmark. The company's flagship product, Lego, consists of variously colored interlocking ...
brick *10 μm –
transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...
width of the
Intel 4004 The Intel 4004 is a 4-bit central processing unit (CPU) released by Intel Corporation in 1971. Sold for US$60, it was the first commercially produced microprocessor, and the first in a long line of Intel CPUs. The 4004 was the first signific ...
, the world's first commercial
microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
*10 μm – mean longest dimension of a human
red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...
*5–20 μm –
dust mite House dust mites (HDM, or simply dust mites) are various species of acariform mites belonging to the family Pyroglyphidae that are found in association with dust in dwellings. They are known for causing allergies. Biology Species The current ...
excreta *10.6 μm – wavelength of light emitted by a
carbon dioxide laser The carbon-dioxide laser (CO2 laser) was one of the earliest gas lasers to be developed. It was invented by Kumar Patel of Bell Labs in 1964 and is still one of the most useful types of laser. Carbon-dioxide lasers are the highest-power continu ...
*15 μm – width of
silk Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the co ...
fibre *17 μm – minimum width of a strand of human hair *17.6 μm – one twip, a unit of length in typography *10 to 55 μm – width of
wool Wool is the textile fibre obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have properties similar to animal wool. A ...
fibre *25.4 μm – 1/1,000 inch, commonly referred to as 1 mil in the U.S. and 1
thou The word ''thou'' is a second-person singular pronoun in English. It is now largely archaic, having been replaced in most contexts by the word ''you'', although it remains in use in parts of Northern England and in Scots (). ''Thou'' is the ...
in the UK *30 μm – length of a human
skin cell Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...
*50 μm – typical length of ''
Euglena gracilis ''Euglena gracilis'' is a freshwater species of single-celled alga in the genus '' Euglena''. It has secondary chloroplasts, and is a mixotroph able to feed by photosynthesis or phagocytosis. It has a highly flexible cell surface, allowing it to ...
'', a flagellate protist *50 μm – typical length of a human
liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it i ...
cell, an average-sized body cell *50 μm – length of a
silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel whe ...
particle *60 μm – length of a
sperm cell Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, wh ...
*70 to 180 μm – thickness of paper


100 micrometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10−4 m and 10−3 m (100  μm and 1  mm). The term ''myriometre'' (abbr. mom, equivalent to 100 micrometres; frequently confused with the ''
myriametre The following are examples of orders of magnitude for different lengths. __TOC__ Overview Detailed list To help compare different orders of magnitude, the following list describes various lengths between 1.6 \times 10^ metres and 10^ ...
'', 10 kilometres) is deprecated; the decimal metric prefix myrio- is obsolete and was not included among the
prefixes A prefix is an affix which is placed before the stem of a word. Adding it to the beginning of one word changes it into another word. For example, when the prefix ''un-'' is added to the word ''happy'', it creates the word ''unhappy''. Particu ...
when the
International System of Units The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. E ...
was introduced in 1960. *100 μm – 1/10 of a millimetre *100 μm – 0.00394 inches *100 μm – smallest distance that can be seen with the
naked eye Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal ...
*100 μm – average diameter of a strand of
human hair Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and fin ...
*100 μm – thickness of a coat of
paint Paint is any pigmented liquid, liquefiable, or solid mastic composition that, after application to a substrate in a thin layer, converts to a solid film. It is most commonly used to protect, color, or provide texture. Paint can be made in man ...
*100 μm – length of a
dust Dust is made of fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind (an aeolian process), volcanic eruptions, and pollution. Dust in homes ...
particle *120 μm – the
geometric mean In mathematics, the geometric mean is a mean or average which indicates a central tendency of a set of numbers by using the product of their values (as opposed to the arithmetic mean which uses their sum). The geometric mean is defined as the ...
of the Planck length and the diameter of the observable universe: *120 μm – diameter of a
human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, an ...
ovum The egg cell, or ovum (plural ova), is the female reproductive cell, or gamete, in most anisogamous organisms (organisms that reproduce sexually with a larger, female gamete and a smaller, male one). The term is used when the female gamete is ...
*170 μm – length of the largest
sperm cell Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, wh ...
in nature, belonging to the '' Drosophila bifurca'' fruit fly *181 μm – maximum width of a strand of human hair *100–400 μm – length of Demodex mites living in human
hair follicle The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between h ...
s *175–200 μm – typical thickness of a
solar cell A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.
. *200 μm – typical length of '' Paramecium caudatum'', a ciliate protist *200 μm – nominal width of the smallest commonly available mechanical pencil lead (0.2 mm) *250–300 μm – length of a
dust mite House dust mites (HDM, or simply dust mites) are various species of acariform mites belonging to the family Pyroglyphidae that are found in association with dust in dwellings. They are known for causing allergies. Biology Species The current ...
*340 μm – length of a
pixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the sm ...
on a 17-inch monitor with a resolution of 1024×768 *500 μm – typical length of ''
Amoeba proteus ''Amoeba proteus'' is a large species of amoeba closely related to another genus of giant amoebae, ''Chaos''. As such, the species is sometimes given the alternative scientific name ''Chaos diffluens''. This protozoan uses extensions called pseud ...
'', an amoeboid protist * *500 μm – average length of a grain of
sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...
*500 μm – average length of a grain of
salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantiti ...
*500 μm – average length of a grain of
sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double s ...
*560 μm – thickness of the central area of a human
cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical powe ...
*750 μm – diameter of a
Thiomargarita namibiensis ''Thiomargarita namibiensis'' is a Gram-negative coccoid bacterium, found in the ocean sediments of the continental shelf of Namibia. It is the second largest bacterium ever discovered, as a rule in diameter, but sometimes attaining . Cells of ...
, the largest bacteria known *760 μm – thickness of an
identification card An identity document (also called ID or colloquially as papers) is any document that may be used to prove a person's identity. If issued in a small, standard credit card size form, it is usually called an identity card (IC, ID card, citizen ca ...


1 millimetre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−3 m and 10−2 m (1 mm and 1 cm). *1.0 mm – 1/1,000 of a metre *1.0 mm – 0.03937
inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es or 5/127 (exactly) *1.0 mm – side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 1 mm² *1.0 mm – diameter of a pinhead *1.5 mm – average length of a flea *2.54 mm – distance between pins on old
dual in-line package In microelectronics, a dual in-line package (DIP or DIL), is an electronic component package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board (P ...
(DIP) electronic components *5 mm – length of an average red ant *5 mm – diameter of an average grain of rice *
5.56×45mm NATO The 5.56×45mm NATO (official NATO nomenclature 5.56 NATO, but often pronounced "five-five-six") is a rimless bottlenecked intermediate cartridge family developed in the late 1970s in Belgium by FN Herstal. It consists of the SS109, L110, a ...
– standard ammunition size *6 mm – approximate width of a pencil *7 mm – length of a ''
Paedophryne amauensis ''Paedophryne amauensis'' is a species of microhylid frog endemic to eastern Papua New Guinea. At in snout-to-vent length, it is considered the world's smallest known vertebrate. (See also Ecological guild.) The species was listed in the '' ...
'', the smallest-known vertebrate *7.1 mm – length of a sunflower seed *
7.62×51mm NATO The 7.62×51mm NATO (official NATO nomenclature 7.62 NATO) is a rimless, bottlenecked rifle cartridge. It is a standard for small arms among NATO countries. First developed in the 1950s, the cartridge had first been introduced in U.S. service fo ...
– common military ammunition size *8 mm – width of old-format home movie film *8 mm – length of a ''
Paedocypris progenetica ''Paedocypris progenetica'' is a species of tiny cyprinid fish endemic to the Indonesian islands of Sumatra and Bintan where it is found in peat swamps and blackwater streams. It was discovered by Singaporean ichthyologist Heok Hui Tan. He has ...
'', the smallest-known fish


1 centimetre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10−2 m and 10−1 m (1 cm and 1 dm). *1 cm – 10
millimetres 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British English spelling differences#-re, -er, ...
*1 cm – 0.39
inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es *1 cm – edge of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 1 cm2 *1 cm – edge of a cube of volume 1 mL *1 cm – length of a coffee bean *1 cm – approximate width of average fingernail *1.2 cm – length of a bee *1.2 cm – diameter of a die *1.5 cm – length of a very large mosquito *1.6 cm – length of a Jaragua Sphaero, a very small reptile *1.7 cm – length of a Thorius arboreus, the smallest salamander *2 cm – approximate width of an adult human finger *2.54 cm – 1 inch *3.08568 cm – 1 attoparsec (10−18
parsec The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (au), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, a ...
s) *3.4 cm – length of a quail egg *3.5 cm – width of film commonly used in motion pictures and still photography *3.78 cm – amount of distance the Moon moves away from Earth each year *4.3 cm – minimum diameter of a golf ball *5 cm – usual diameter of a chicken egg *5 cm – height of a hummingbird, the smallest-known bird *5.5 × 5.5 × 5.5 cm – dimensions of a 3x3x3 Rubik's cube *6.1 cm – average height of an apple *7.3–7.5 cm – diameter of a baseball *8.6 cm × 5.4 cm – dimensions of a standard credit card *9 cm – length of a speckled padloper, the smallest-known turtle


1 decimetre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to (). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10
centimetre 330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter. A centimetre (international spelling) or centimeter (American spellin ...
s and 100 centimetres (10−1 metre and 1 metre).


Conversions

10 centimetres (abbreviated to 10 cm) is equal to: *1
decimetre The decimetre (symbol dm) or decimeter (American English) is a unit of length in the International System of Units (SI), equal to one tenth of a metre, ten centimetres, 100 millimetres or 3.937 inches. The common non-SI metric unit of volume ...
(dm), a term not in common use (1 L = 1 dm3.) *100
millimetre file:EM Spectrum Properties edit.svg, 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British Eng ...
s *3.9
inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es *a side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 0.01 m2 *the edge of a cube with a volume of m3 (1 L)


Wavelengths

*10 cm = 1.0 dm – wavelength of the highest
UHF Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (on ...
radio frequency, 3 GHz *12 cm = 1.2 dm – wavelength of the 2.45 GHz ISM radio band *21 cm = 2.1 dm – wavelength of the 1.4 GHz hydrogen emission line, a
hyperfine In atomic physics, hyperfine structure is defined by small shifts in otherwise degenerate energy levels and the resulting splittings in those energy levels of atoms, molecules, and ions, due to electromagnetic multipole interaction between the nuc ...
transition of the hydrogen atom *100 cm = 10 dm – wavelength of the lowest UHF radio frequency, 300 MHz


Human-defined scales and structures

*10.16 cm = 1.016 dm – 1
hand A hand is a prehensile, multi-fingered appendage located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each " ...
used in measuring height of horses (4 inches) *12 cm = 1.2 dm – diameter of a compact disc (CD) (= 120 mm) *15 cm = 1.5 dm – length of a Bic pen with cap on *22 cm = 2.2 dm – diameter of a typical association football (soccer ball) *30 cm = 3 dm – typical school-use ruler length (= 300 mm) *30.48 cm = 3.048 dm – 1
foot The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...
(measure) *60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (= 600 mm) *90 cm = 9 dm – average length of a rapier, a fencing sword *91.44 cm = 9.144 dm – one yard (measure)


Nature

*10 cm = 1 dm – diameter of the human
cervix The cervix or cervix uteri (Latin, 'neck of the uterus') is the lower part of the uterus (womb) in the human female reproductive system. The cervix is usually 2 to 3 cm long (~1 inch) and roughly cylindrical in shape, which changes during ...
upon entering the second stage of labour *11 cm = 1.1 dm – diameter of an average potato in the US *13 cm = 1.3 dm – body length of a Goliath birdeater *15 cm = 1.5 dm – approximate size of largest beetle species *19 cm = 1.9 dm – length of a banana *26.3 cm = 2.6 dm – length of average male human foot *29.98 cm = 2.998 dm – distance light in vacuum travels in one
nanosecond A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, of a second, or 10 seconds. The term combines the SI prefix ''nano-'' indicating a 1 billionth submultiple of an SI unit ( ...
*30 cm = 3.0 dm – maximum leg length of a Goliath birdeater *31 cm = 3.1 dm – wingspan of largest butterfly species ''Ornithoptera alexandrae'' *46 cm = 4.6 dm – length of an average domestic cat *50 to 65 cm = 5–6.5 dm – a coati's tail *66 cm = 6.6 dm – length of the longest pine cones (produced by the sugar pine)


Astronomical

*84 cm = 8.4 dm – approximate diameter of 2008 TS26, a meteoroid


1 metre

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between one
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
and ten metres. Light, in vacuum, travels 1 metre in , or of a second.


Conversions

1
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
is: *10
decimetre The decimetre (symbol dm) or decimeter (American English) is a unit of length in the International System of Units (SI), equal to one tenth of a metre, ten centimetres, 100 millimetres or 3.937 inches. The common non-SI metric unit of volume ...
s *100
centimetre 330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter. A centimetre (international spelling) or centimeter (American spellin ...
s *1,000
millimetre file:EM Spectrum Properties edit.svg, 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British Eng ...
s *39.37
inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es *3.28
feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...
*1.1 yards *side of
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
with area 1 m2 *edge of cube with surface area 6 m2 and volume 1 m3 *radius of
circle A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. Equivalently, it is the curve traced out by a point that moves in a plane so that its distance from a given point is con ...
with area π m2 *radius of
sphere A sphere () is a geometrical object that is a three-dimensional analogue to a two-dimensional circle. A sphere is the set of points that are all at the same distance from a given point in three-dimensional space.. That given point is the ...
with surface area 4π m2 and volume 4/3π m3


Human-defined scales and structures

*1 m – approximate height of the top part of a doorknob on a door *1 m – diameter of a very large beach ball *1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 8 in *2.5 m – distance from the floor to the ceiling in an average residential house *2.7 m – length of the Starr Bumble Bee II, the smallest plane *2.77–3.44 m – wavelength of the broadcast radio FM band 87–108 MHz *3.05 m – the length of an old Mini *8.38 m – the length of a London Bus (
AEC Routemaster The AEC Routemaster is a front-engined double-decker bus that was designed by London Transport and built by the Associated Equipment Company (AEC) and Park Royal Vehicles. The first prototype was completed in September 1954 and the last one ...
)


Sports

*2.44 m – height of an association football goal *2.45 m – highest high jump by a human (Javier Sotomayor) *3.05 m – (10 feet) height of the basket in basketball *8.95 m – longest long jump by a human (Mike Powell)


Nature

*1 m – height of ''
Homo floresiensis ''Homo floresiensis'' also known as "Flores Man"; nicknamed "Hobbit") is an extinct species of small archaic human that inhabited the island of Flores, Indonesia, until the arrival of modern humans about 50,000 years ago. The remains of an i ...
'' (the "Hobbit") *1.15 m – a pizote (mammal) *1.63 m – (5 feet 4 inches) (or 64 inches) – height of average U.S. female human (source: U.S. Centers for Disease Control and Prevention (CDC)) *1.75 m – (5 feet 8 inches) – height of average U.S. male human (source: U.S. CDC as per female above) *2.5 m – height of a sunflower *2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow) *3.63 m – the record wingspan]for living birds (a wandering albatross) *5 m – length of an elephant *5.2 m – height of a giraffe *5.5 m – height of a ''
Baluchitherium ''Paraceratherium'' is an extinct genus of hornless rhinoceros. It is one of the largest terrestrial mammals that has existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered ...
'', the largest land mammal ever lived *6.5 m – wingspan of '' Argentavis'', the largest flying bird known *7.4 m – wingspan of '' Pelagornis,'' the bird with longest wingspan ever. *7.5 m – approximate length of the human gastrointestinal tract


Astronomical

*3–6 m – approximate diameter of , a meteoroid *4.1 m – diameter of
2008 TC3 (Catalina Sky Survey temporary designation 8TA9D69) was an , diameter asteroid that entered Earth's atmosphere on October 7, 2008. It exploded at an estimated above the Nubian Desert in Sudan. Some 600 meteorites, weighing a total of , were ...
, a small asteroid that flew into the Earth's atmosphere on October 7, 2008


1 decametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 10 
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (101 m). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists lengths between 10 and 100 metres.


Conversions

10 metres (very rarely termed a
decametre A decametre ( International spelling as used by the International Bureau of Weights and Measures and by most English speaking countries, United States spelling dekameter or decameter,), symbol dam ("da" for the SI prefix deca-, "m" for the SI ...
which is abbreviated as dam) is equal to: *10 metres *100
decimetre The decimetre (symbol dm) or decimeter (American English) is a unit of length in the International System of Units (SI), equal to one tenth of a metre, ten centimetres, 100 millimetres or 3.937 inches. The common non-SI metric unit of volume ...
s *1,000
centimetre 330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter. A centimetre (international spelling) or centimeter (American spellin ...
s *10,000
millimetre file:EM Spectrum Properties edit.svg, 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British Eng ...
s *32.8
feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...
*11
yards The yard (symbol: yd) is an English unit of length in both the British imperial and US customary systems of measurement equalling 3 feet or 36 inches. Since 1959 it has been by international agreement standardized as exactly 0. ...
*side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
with area 100 m²


Human-defined scales and structures

*10 metres – wavelength of the highest shortwave radio frequency, 30 M Hz *23 metres – height of the obelisk of the Place de la Concorde, Paris, France *25 metres – wavelength of the broadcast radio shortwave band at 12 MHz *29 metres – height of the lighthouse at Savudrija, Croatia *31 metres – wavelength of the broadcast radio shortwave band at 9.7 MHz *34 metres – height of the
Split Point Lighthouse Split Point Lighthouse is a lighthouse located in Aireys Inlet, a small town on the Great Ocean Road, Victoria, Australia. History Originally called Eagles Nest Point, the lighthouse was constructed in 1891. For 27 years, three lighthouse kee ...
in Aireys Inlet, Victoria, Australia *40 metres – average depth beneath the seabed of the
Channel tunnel The Channel Tunnel (french: Tunnel sous la Manche), also known as the Chunnel, is a railway tunnel that connects Folkestone (Kent, England, UK) with Coquelles ( Hauts-de-France, France) beneath the English Channel at the Strait of Dover. ...
*49 metres – wavelength of the broadcast radio shortwave band at 6.1 MHz *50 metres – length of a road train *55 metres – height of the
Leaning Tower of Pisa The Leaning Tower of Pisa ( it, torre pendente di Pisa), or simply, the Tower of Pisa (''torre di Pisa'' ), is the ''campanile'', or freestanding bell tower, of Pisa Cathedral. It is known for its nearly four-degree lean, the result of an unsta ...
*62.5 metres – height of
Pyramid of Djoser The pyramid of Djoser (or Djeser and Zoser), sometimes called the Step Pyramid of Djoser, is an archaeological site in the Saqqara necropolis, Egypt, northwest of the ruins of Memphis. The 6-tier, 4-sided structure is the earliest colossal stone ...
*64 metres – wingspan of a Boeing 747-400 *69 metres – wingspan of an Antonov An-124 Ruslan *70 metres – length of the Bayeux Tapestry *70 metres – width of a typical association football field *77 metres – wingspan of a Boeing 747-8 *88.4 metres – wingspan of an Antonov An-225 ''Mriya'' transport aircraft *93 metres – height of the Statue of Liberty *96 metres – height of Big Ben *100 metres – wavelength of the lowest shortwave radio frequency, 3 MHz


Sports

*11 metres – approximate width of a doubles tennis court *15 metres – width of a standard FIBA basketball court *15.24 metres – width of an NBA]basketball court (50 feet) *18.44 metres – distance between the front of the pitcher's rubber and the rear point of home plate on a baseball field (60 feet, 6 inches) *20 metres – length of cricket pitch (22 yards) *27.43 metres – distance between bases on a baseball field (90 feet) *28 metres – length of a standard FIBA basketball court *28.65 metres – length of an NBA basketball court (94 feet) *49 metres – width of an American football field (53 yards) *59.436 metres – width of a Canadian football field (65 yards) *70 metres – typical width of a soccer field *91 metres – length of an American football field (100 yards, measured between the goal lines)


Nature

*10 metres – average length of human digestive tract *12 metres – length of a whale shark, largest living fish *12 metres – wingspan of a ''
Quetzalcoatlus ''Quetzalcoatlus'' is a genus of pterosaur known from the Late Cretaceous period of North America (Maastrichtian stage); its members were among the largest known flying animals of all time. ''Quetzalcoatlus'' is a member of the Azhdarchidae, a ...
'', a pterosaur *13 metres – length of a giant squid and colossal squid, the largest living invertebrates *15 metres – approximate distance the tropical circles of latitude are moving towards the equator and the polar circles are moving towards the poles each year due to a natural, gradual decrease in the Earth's axial tilt *18 metres – height of a ''
Sauroposeidon ''Sauroposeidon'' ( ; meaning "lizard earthquake god", after the Greek god Poseidon) is a genus of sauropod dinosaur known from several incomplete specimens including a bone bed and fossilized trackways that have been found in the U.S. states of ...
'', the tallest-known dinosaur *20 metres – length of a ''
Leedsichthys ''Leedsichthys'' is an extinct genus of pachycormid fish that lived in the oceans of the Middle to Late Jurassic.Liston, JJ (2004). An overview of the pachycormiform ''Leedsichthys''. In: Arratia G and Tintori A (eds) Mesozoic Fishes 3 - Syste ...
'', the largest-known fish to have lived *21 metres – height of
High Force High Force is a waterfall on the River Tees, near Middleton-in-Teesdale, Teesdale, England. The waterfall is within the North Pennines Area of Outstanding Natural Beauty (AONB) and the European Geopark. The waterfall is part of the historic ...
waterfall in England *33 metres – length of a blue whale, the largest animal on earth, living or extinct, in terms of mass *39 metres – length of a ''
Supersaurus ''Supersaurus'' (meaning "super lizard") is a genus of diplodocid sauropod dinosaur that lived in North America during the Late Jurassic period. The type species, ''S. vivianae'', was first discovered by Vivian Jones of Delta, Colorado, in the ...
'', the longest-known dinosaur and longest vertebrate *52 metres – height of Niagara Falls *55 metres – length of a bootlace worm, the longest-known animal *83 metres – height of a Western hemlock


Astronomical

*30 metres – diameter of , a rapidly spinning meteoroid *30.8568 metres – 1 femtoparsec *32 metres – approximate diameter of
2008 HJ 2008 HJ is a sub-kilometer asteroid, classified as near-Earth object of the Apollo group. It was discovered by Lincoln Laboratory ETS, New Mexico. Observers M. Bezpalko, D. Torres, R. Kracke, G. Spitz, J. Kistler. Richard Miles using the Faulke ...
, a small meteoroid


1 hectometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 100 
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (102 m). To compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists lengths between 100 metres and 1,000 metres (1
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
).


Conversions

100 metres (sometimes termed a hectometre) is equal to: *328
feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...
*one side of a 1 hectare square *a fifth of a modern li, a Chinese unit of measurement *the approximate distance travelled by light in 300
nanosecond A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, of a second, or 10 seconds. The term combines the SI prefix ''nano-'' indicating a 1 billionth submultiple of an SI unit ( ...
s


Human-defined scales and structures

*100 metres – wavelength of the highest medium wave radio frequency, 3 MHz *100 metres – spacing of location marker posts on British motorways *138.8 metres – height of the
Great Pyramid of Giza The Great Pyramid of Giza is the biggest Egyptian pyramids, Egyptian pyramid and the tomb of Fourth Dynasty of Egypt, Fourth Dynasty pharaoh Khufu. Built in the early 26th century BC during a period of around 27 years, the pyramid is the oldes ...
(Pyramid of Cheops) *139 metres – height of the world's tallest roller coaster, Kingda Ka *187 metres – shortest wavelength of the broadcast radio AM band, 1600 kHz *202 metres – length of the
Széchenyi Chain Bridge The Széchenyi Chain Bridge ( hu, Széchenyi lánchíd ) is a chain bridge that spans the River Danube between Buda and Pest, the western and eastern sides of Budapest, the capital of Hungary. Designed by English engineer William Tierney Clark ...
connecting Buda and Pest *318 metres – height of The New York Times Building *318.9 metres – height of the Chrysler Building *328 metres – height of Auckland's Sky Tower, the tallest free-standing structure in the Southern Hemisphere *330 metres – height of the
Eiffel Tower The Eiffel Tower ( ; french: links=yes, tour Eiffel ) is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower. Locally nicknamed "' ...
(including antenna) *341 metres – height of the world's tallest bridge, the Millau Viaduct *390 metres – height of the Empire State Building *400–800 metres – heights of the world's tallest skyscrapers of the past 80 years *458 metres – length of the Knock Nevis, the world's largest supertanker *553.33 metres – height of the CN Tower *555 metres – longest wavelength of the broadcast radio AM band, 540 kHz *630 metres – height of the KVLY-TV mast, second-tallest structure in the world *646 metres – height of the Warsaw radio mast, the world's tallest structure until its collapse in 1991 *828 metres – height of Burj Khalifa, world's tallest structure on 17 January 2009 *1,000 metres – wavelength of the lowest mediumwave radio frequency, 300 kHz


Sports

*100 metres – the distance a very fast human can run in about 10 seconds *100.584 metres – length of a Canadian football field between the goal lines (110 yards) *91.5 metres – 137 metres – length of a soccer field *105 metres – length of football pitch (UEFA stadium categories 3 and 4) *105 metres – length of a typical football field *109.73 metres – total length of an American football field (120 yards, including the end zones) *110–150 metres – the width of an Australian football field *135–185 metres – the length of an Australian football field *137.16 metres – total length of a Canadian football field, including the end zones (150 yards)


Nature

*115.5 metres – height of the world's tallest tree in 2007, the Hyperion sequoia *310 metres – maximum depth of Lake Geneva *340 metres – distance sound travels in air at sea level in one second; see
Speed of sound The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At , the speed of sound in air is about , or one kilometre in or one mile in . It depends strongly on temperature as wel ...
*979 metres – height of the Salto Angel, the world's highest free-falling waterfall (Venezuela) *1500 metres – distance sound travels in water in one second


Astronomical

*270 metres – length of
99942 Apophis 99942 Apophis is a near-Earth asteroid and potentially hazardous asteroid with a diameter of that caused a brief period of concern in December 2004 when initial observations indicated a probability up to 2.7% that it would hit Earth on April&nbs ...
*535 metres – length of
25143 Itokawa 25143 Itokawa (provisional designation ) is a sub-kilometer near-Earth object of the Apollo group and a potentially hazardous asteroid. It was discovered by the LINEAR program in 1998 and later named after Japanese rocket engineer Hideo Itokaw ...
, a small asteroid visited by a spacecraft


1 kilometre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to  
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (103 m). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 1 kilometre and 10 
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s (103 and 104
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s).


Conversions

1
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
(unit symbol km) is equal to: *1,000
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s *0.621371
mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Englis ...
s *1,093.61 yards *3,280.84
feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...
*39,370.1
inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es *100,000
centimetre 330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter. A centimetre (international spelling) or centimeter (American spellin ...
s *1,000,000
millimetre file:EM Spectrum Properties edit.svg, 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British Eng ...
s *Side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 1 km2 *Radius of a
circle A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. Equivalently, it is the curve traced out by a point that moves in a plane so that its distance from a given point is con ...
of area π km2


Human-defined scales and structures

*1 km – wavelength of the highest
long wave In radio, longwave, long wave or long-wave, and commonly abbreviated LW, refers to parts of the radio spectrum with wavelengths longer than what was originally called the medium-wave broadcasting band. The term is historic, dating from the e ...
radio frequency,
300 __NOTOC__ Year 300 ( CCC) was a leap year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Constantius and Valerius (or, less frequently, year 1053 ''Ab ...
kHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
*1.280 km – span of the
Golden Gate Bridge The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the strait connecting San Francisco Bay and the Pacific Ocean. The structure links the U.S. city of San Francisco, California—the northern tip of the San Francisco Penin ...
(distance between towers) *1.609 km – 1 statute mile *1.852 km – 1
nautical mile A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters. Historically, it was defined as the meridian arc length corresponding to one minute ( of a degree) of latitude. Today t ...
, equal to 1
arcminute A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The n ...
of
latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north ...
at the surface of the Earth *1.991 km – span of the
Akashi Kaikyō Bridge The is a suspension bridge which links the city of Kobe on the Japanese island of Honshu to Iwaya on Awaji Island. It is part of the Kobe-Awaji-Naruto Expressway, and crosses the busy and turbulent Akashi Strait (''Akashi Kaikyō'' in Japanes ...
*2.309 km – axial length of the
Three Gorges Dam The Three Gorges Dam is a hydroelectric gravity dam that spans the Yangtze River by the town of Sandouping, in Yiling District, Yichang, Hubei province, central China, downstream of the Three Gorges. The Three Gorges Dam has been the world ...
, the largest
dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...
in the world *3.991 km – length of the
Akashi Kaikyō Bridge The is a suspension bridge which links the city of Kobe on the Japanese island of Honshu to Iwaya on Awaji Island. It is part of the Kobe-Awaji-Naruto Expressway, and crosses the busy and turbulent Akashi Strait (''Akashi Kaikyō'' in Japanes ...
, longest
suspension bridge A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridges, which lack vertical ...
in the world *5.072 km – height of
Tanggula Mountain Pass The Tanggu La, Tangla Pass, or Tanggu Pass (; bo, གདང་ལ) is a wide mountain pass in Southwest China over in elevation, which utilized by both the Qinghai–Tibet Highway and Qinghai–Tibet Railway to cross the Tanggula Mountains. T ...
, below highest peak in the
Tanggula Mountains The Tanggula ( Chinese: , p ''Tánggǔlāshān'', or , p ''Tánggǔlāshānmài''), Tangla, Tanglha, or Dangla Mountains ( Tibetan: , w ''Gdang La'', z ''Dang La'') are a mountain range in the central part of the ...
, highest
railway Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prep ...
pass in the world *5.727 km – height of Cerro Aucanquilcha, highest road in the world, located in
Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...
* 98 airports have paved runways from 4 km to 5.5 km in length. *8 km – length of
Palm Jebel Ali Palm Jebel Ali () is an artificial archipelago in Dubai, United Arab Emirates which began construction in October 2002, was originally planned to be completed by mid-2008 and has been on hold since. Creative Kingdom provided master planning servi ...
, an
artificial island An artificial island is an island that has been constructed by people rather than formed by natural means. Artificial islands may vary in size from small islets reclaimed solely to support a single pillar of a building or structure to those tha ...
built off the coast of
Dubai Dubai (, ; ar, دبي, translit=Dubayy, , ) is the most populous city in the United Arab Emirates (UAE) and the capital of the Emirate of Dubai, the most populated of the 7 emirates of the United Arab Emirates.The Government and Politics o ...
*9.8 km – length of
The World In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the worl ...
, an artificial archipelago that is also built off the coast of
Dubai Dubai (, ; ar, دبي, translit=Dubayy, , ) is the most populous city in the United Arab Emirates (UAE) and the capital of the Emirate of Dubai, the most populated of the 7 emirates of the United Arab Emirates.The Government and Politics o ...
, whose islands resemble a
world map A world map is a map of most or all of the surface of Earth. World maps, because of their scale, must deal with the problem of projection. Maps rendered in two dimensions by necessity distort the display of the three-dimensional surface of th ...


Geographical

*1.637 km – deepest dive of
Lake Baikal Lake Baikal (, russian: Oзеро Байкал, Ozero Baykal ); mn, Байгал нуур, Baigal nuur) is a rift lake in Russia. It is situated in southern Siberia, between the federal subjects of Irkutsk Oblast to the northwest and the Rep ...
in
Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eight ...
, the world's largest
freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does inclu ...
lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger ...
*2.228 km – height of
Mount Kosciuszko Mount Kosciuszko ( ; Ngarigo: , ), previously spelled Mount Kosciusko, is mainland Australia's tallest mountain, at 2,228 metres (7,310 ft) above sea level. It is located on the Main Range of the Snowy Mountains in Kosciuszko National P ...
, highest point on mainland Australia *Most of
Manhattan Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the List of counties in New York, origin ...
is from 3 to 4 km wide. *4.810 km – height of
Mont Blanc Mont Blanc (french: Mont Blanc ; it, Monte Bianco , both meaning "white mountain") is the highest mountain in the Alps and Western Europe, rising above sea level. It is the second-most prominent mountain in Europe, after Mount Elbrus, and it ...
, highest peak in the
Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Sw ...
*4.884 km – height of
Carstensz Pyramid Puncak Jaya (; literally "Glorious Peak") or Carstensz Pyramid, Mount Jayawijaya or Mount Carstensz () on the island of New Guinea, with an elevation of , is the highest mountain peak of an island on Earth. The mountain is located in the Sud ...
, highest peak in
Oceania Oceania (, , ) is a geographical region that includes Australasia, Melanesia, Micronesia, and Polynesia. Spanning the Eastern and Western hemispheres, Oceania is estimated to have a land area of and a population of around 44.5 million as ...
*4.892 km – height of
Mount Vinson Vinson Massif () is a large mountain massif in Antarctica that is long and wide and lies within the Sentinel Range of the Ellsworth Mountains. It overlooks the Ronne Ice Shelf near the base of the Antarctic Peninsula. The massif is located a ...
, highest peak in
Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
*5.610 km – height of
Mount Damavand Mount Damavand ( fa, دماوند ) is a dormant stratovolcano, the highest peak in Iran and Western Asia and the highest volcano in Asia and the 2nd highest volcano in the Eastern Hemisphere (after Mount Kilimanjaro), at an elevation of ...
, highest peak in
Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkme ...
*5.642 km – height of
Mount Elbrus Mount Elbrus ( rus, links=no, Эльбрус, r=Elbrus, p=ɪlʲˈbrus; kbd, Ӏуащхьэмахуэ, 'uaşhəmaxuə; krc, Минги тау, Mingi Taw) is the highest and most prominent peak in Russia and Europe. It is situated in the we ...
, highest peak in Europe *5.895 km – height of
Mount Kilimanjaro Mount Kilimanjaro () is a dormant volcano in Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira. It is the highest mountain in Africa and the highest free-standing mountain above sea level in the world: above sea level and ab ...
, highest peak in
Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
*6.081 km – height of
Mount Logan Mount Logan () is the highest mountain in Canada and the second-highest peak in North America after Denali. The mountain was named after Sir William Edmond Logan, a Canadian geologist and founder of the Geological Survey of Canada (GSC). Moun ...
, highest peak in Canada *6.190 km – height of
Denali Denali (; also known as Mount McKinley, its former official name) is the highest mountain peak in North America, with a summit elevation of above sea level. With a topographic prominence of and a topographic isolation of , Denali is the thi ...
, highest peak in
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the C ...
*6.959 km – height of
Aconcagua Aconcagua () is a mountain in the Principal Cordillera of the Andes mountain range, in Mendoza Province, Argentina. It is the highest mountain in the Americas, the highest outside Asia, and the highest in the Southern Hemisphere with a summ ...
, highest peak in South America *7.5 km – depth of
Cayman Trench __NOTOC__ The Cayman Trough (also known as the Cayman Trench, Bartlett Deep and Bartlett Trough) is a complex transform fault zone pull-apart basin which contains a small spreading ridge, the Mid-Cayman Rise, on the floor of the western Caribbe ...
, deepest point in the
Caribbean Sea The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Zee; pap, Laman Karibe) is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico ...
*8.848 km – height of
Mount Everest Mount Everest (; Tibetan: ''Chomolungma'' ; ) is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The China–Nepal border runs across its summit point. Its elevation (snow heig ...
, highest peak on
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
, on the border between
Nepal Nepal (; ne, नेपाल ), formerly the Federal Democratic Republic of Nepal ( ne, सङ्घीय लोकतान्त्रिक गणतन्त्र नेपाल ), is a landlocked country in South Asia. It is mai ...
and China


Astronomical

*1 km – diameter of
1620 Geographos 1620 Geographos (), provisional designation , is a highly elongated, stony asteroid, near-Earth object and potentially hazardous asteroid of the Apollo group, with a mean-diameter of approximately . It was discovered on 14 September 1951, by as ...
*1 km – very approximate size of the smallest-known
moons of Jupiter There are 82 known Natural satellite, moons of Jupiter, not counting a number of moonlets likely shed from the inner moons. All together, they form a satellite system (astronomy), satellite system which is called the Jovian system. The most mas ...
*1.4 km – diameter of Dactyl, the first confirmed
asteroid moon A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. , there are 457 minor planets known or suspected to have moons. Discoveries of minor-planet moons (and binary objects, in general) are important ...
*4.8 km – diameter of
5535 Annefrank 5535 Annefrank (), provisional designation , is a stony Florian asteroid and suspected contact binary from the inner asteroid belt, approximately 4.5 kilometers in diameter. It was used as a target to practice the flyby technique that the Stard ...
, an inner belt asteroid *5 km – diameter of
3753 Cruithne 3753 Cruithne is a Q-type, Aten asteroid in orbit around the Sun in 1:1 orbital resonance with Earth, making it a co-orbital object. It is an asteroid that, relative to Earth, orbits the Sun in a bean-shaped orbit that effectively describes a ...
*5 km – length of
PSR B1257+12 PSR B1257+12, previously designated PSR 1257+12, alternatively designated PSR J1300+1240, is a millisecond pulsar located 2,300 light-years from the Sun in the constellation of Virgo, rotating at about 161 times per second (faster than a ...
*8 km – diameter of
Themisto In Greek mythology, Themisto (; Ancient Greek: Θεμιστώ) was a Thessalin princess as the daughter of King Hypseus of Lapiths Apollodorus, 1.9.2 and the naiad Chlidanope. Her name is derived from the Ancient Greek word: "θεμιστος" ...
, one of
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
's moons *8 km – diameter of the Vela Pulsar *8.6 km – diameter of Callirrhoe, also known as Jupiter XVII *9.737 km – length of
PSR B1919+21 PSR B1919+21 is a pulsar with a period of 1.3373 seconds and a pulse width of 0.04 seconds. Discovered by Jocelyn Bell Burnell on 28 November 1967, it is the first discovered radio pulsar. The power and regularity of the signals were ...


10 kilometres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 10 and 100
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s (104 to 105
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s). The ''myriametre'' (Website based on ''Alte Meß- und Währungssysteme aus dem deutschen Sprachgebiet'', ) (sometimes also spelled ''myriometre''; 10,000 metres) is a deprecated unit name; the decimal metric prefix
myria- Myria- (symbol my) is a now obsolete decimal metric prefix denoting a factor of 104 (ten thousand). It originates from the Greek μύριοι (''mýrioi'') (myriad). The prefix was part of the original metric system adopted by France in 1795, bu ...
(sometimes also written as myrio-) is obsolete and not included among the
prefixes A prefix is an affix which is placed before the stem of a word. Adding it to the beginning of one word changes it into another word. For example, when the prefix ''un-'' is added to the word ''happy'', it creates the word ''unhappy''. Particu ...
when the
International System of Units The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. E ...
was introduced in 1960.


Conversions

10 kilometres is equal to: *10,000
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s *6.2
mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Englis ...
s *1 ''mil (the
Scandinavian mile A Scandinavian mile ( Norwegian and sv, mil, [], like "meal") is a unit of length common in Norway and Sweden, but not Denmark. Today, it is standardised as 1 being , but it had different values in the past. The word is derived from the same ...
)'', now standardized as 10 km: **1 mil, the unit of measure commonly used in
Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and th ...
and
Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
Haugen, Einar, ''Norwegian English Dictionary,'' 1965, Oslo: Universitetsforlaget and Madison:
University of Wisconsin Press The University of Wisconsin Press (sometimes abbreviated as UW Press) is a non-profit university press publishing peer-reviewed books and journals. It publishes work by scholars from the global academic community; works of fiction, memoir and po ...
, s.v. mil
used to be 11,295 m in Norway and 10,688 m in Sweden. *'' farsang'', unit of measure commonly used in
Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkme ...
and
Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula in ...


Sports

*42.195 km – length of the
marathon The marathon is a long-distance foot race with a distance of , usually run as a road race, but the distance can be covered on trail routes. The marathon can be completed by running or with a run/walk strategy. There are also wheelchair div ...


Human-defined scales and structures

*18 km – cruising altitude of Concorde *27 km – circumference of the
Large Hadron Collider The Large Hadron Collider (LHC) is the world's largest and highest-energy particle collider. It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and hundre ...
, the largest and highest energy
particle accelerator A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies, and to contain them in well-defined beams. Large accelerators are used for fundamental research in particle ...
*34.668 km – highest manned
balloon A balloon is a flexible bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, and air. For special tasks, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or light s ...
flight (Malcolm D. Ross and Victor E. Prather on 4 May 1961) *38.422 km – length of the Second
Lake Pontchartrain Causeway The Lake Pontchartrain Causeway (french: Chaussée du lac Pontchartrain), also known simply as The Causeway, is a fixed link composed of two parallel bridges crossing Lake Pontchartrain in southeastern Louisiana, United States. The longer of th ...
in
Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is border ...
, US *39 km – undersea portion of the
Channel tunnel The Channel Tunnel (french: Tunnel sous la Manche), also known as the Chunnel, is a railway tunnel that connects Folkestone (Kent, England, UK) with Coquelles ( Hauts-de-France, France) beneath the English Channel at the Strait of Dover. ...
*53.9 km – length of the
Seikan Tunnel The Seikan Tunnel ( ja, 青函トンネル, or , ), is a dual-gauge railway tunnel in Japan, with a portion under the seabed of the Tsugaru Strait, which separates Aomori Prefecture on the main Japanese island of Honshu from the northern isl ...
, , the longest rail tunnel in the world *77 km – rough total length of the Panama Canal


Geographical

*10 km – height of
Mauna Kea Mauna Kea ( or ; ; abbreviation for ''Mauna a Wākea''); is a dormant volcano on the island of Hawaii. Its peak is above sea level, making it the highest point in the state of Hawaii and second-highest peak of an island on Earth. The peak is ...
in
Hawaii Hawaii ( ; haw, Hawaii or ) is a U.S. state, state in the Western United States, Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is ...
, measured from its base on the ocean floor *11 km – deepest-known point of the ocean,
Challenger Deep The Challenger Deep is the deepest-known point of the seabed of Earth, with a depth of by direct measurement from deep-diving submersibles, remotely operated underwater vehicles and benthic landers, and (sometimes) slightly more by sonar bath ...
in the
Mariana Trench The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about in length and in width. The maximum known ...
*11 km – average height of the
troposphere The troposphere is the first and lowest layer of the atmosphere of the Earth, and contains 75% of the total mass of the planetary atmosphere, 99% of the total mass of water vapour and aerosols, and is where most weather phenomena occur. From t ...
*14 km – width of the
Gibraltar strait The Strait of Gibraltar ( ar, مضيق جبل طارق, Maḍīq Jabal Ṭāriq; es, Estrecho de Gibraltar, Archaic: Pillars of Hercules), also known as the Straits of Gibraltar, is a narrow strait that connects the Atlantic Ocean to the Medi ...
*21 km – length of
Manhattan Manhattan (), known regionally as the City, is the most densely populated and geographically smallest of the five boroughs of New York City. The borough is also coextensive with New York County, one of the List of counties in New York, origin ...
*23 km – depth of the largest earthquake ever recorded in the United Kingdom, in 1931 at the
Dogger Bank Dogger Bank (Dutch: ''Doggersbank'', German: ''Doggerbank'', Danish: ''Doggerbanke'') is a large sandbank in a shallow area of the North Sea about off the east coast of England. During the last ice age the bank was part of a large landmass ...
of the
North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegia ...
*34 km – narrowest width of the
English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" ( Cotentinais) or (Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...
at the
Strait of Dover The Strait of Dover or Dover Strait (french: Pas de Calais - ''Strait of Calais''), is the strait at the narrowest part of the English Channel, marking the boundary between the Channel and the North Sea, separating Great Britain from continent ...
*50 km – approximate height of the
stratosphere The stratosphere () is the second layer of the atmosphere of the Earth, located above the troposphere and below the mesosphere. The stratosphere is an atmospheric layer composed of stratified temperature layers, with the warm layers of air h ...
*90 km – width of the Bering Strait


Astronomical

*10 km – diameter of the most massive
neutron star A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich. Except for black holes and some hypothetical objects (e.g. whit ...
s (3–5
solar mass The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass o ...
es) *13 km – mean diameter of Deimos, the smaller moon of
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...
*20 km – diameter of the least massive neutron stars (1.44 solar masses) *20 km – diameter of Leda, one of
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
's moons *20 km – diameter of Pan, one of
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
's moons *22 km – diameter of Phobos, the larger moon of
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...
*27 km – height of
Olympus Mons Olympus Mons (; Latin for Mount Olympus) is a large shield volcano on Mars. The volcano has a height of over 21.9 km (13.6 mi or 72,000 ft) as measured by the Mars Orbiter Laser Altimeter (MOLA). Olympus Mons is about two and a hal ...
above the
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...
reference level, the highest-known mountain of the
Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...
*30.8568 km – 1 picoparsec *43 km – diameter difference of
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
's
equatorial bulge An equatorial bulge is a difference between the equatorial and polar diameters of a planet, due to the centrifugal force exerted by the rotation about the body's axis. A rotating body tends to form an oblate spheroid rather than a sphere. On Ear ...
*66 km – diameter of
Naiad In Greek mythology, the naiads (; grc-gre, ναϊάδες, naïádes) are a type of female spirit, or nymph, presiding over fountains, wells, springs, streams, brooks and other bodies of fresh water. They are distinct from river gods, who ...
, the innermost of
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
's moons


100 kilometres

A length of ''100 kilometres'' (about 62 miles), as a rough amount, is relatively common in measurements on Earth and for some astronomical objects. It is the altitude at which the FAI defines
spaceflight Spaceflight (or space flight) is an application of astronautics to fly spacecraft into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in ...
to begin. To help compare
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s between 100 and 1,000
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s (105 and 106
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s).


Conversions

A distance of 100 kilometres is equal to about 62 miles (or ).


Human-defined scales and structures

*100 km – the
Karman line Karman or Kármán is a Hungarian surname. Notable people with the surname include: * Harvey Karman (20th century), inventor of the Karman cannula * Janice Karman (born 1954), American film producer, record producer, singer, and voice artist * J ...
: the official boundary of
outer space Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, pred ...
*105 km – distance from
Giridih Giridih is headquarters of the Giridih district of Jharkhand state, India. The city of Giridih is known for its industrial and health sectors, as well as its scenic beauty. Giridih houses the Giridih Coalfield which is one of the oldest coalfi ...
to Bokaro *109 km – length of
High Speed 1 High Speed 1 (HS1), legally the Channel Tunnel Rail Link (CTRL), is a high-speed railway linking London with the Channel Tunnel. It is part of a line carrying international passenger traffic between the United Kingdom and mainland Europe; ...
between London and the Channel Tunnel *130 km – range of a
Scud A Scud missile is one of a series of tactical ballistic missiles developed by the Soviet Union during the Cold War. It was exported widely to both Second and Third World countries. The term comes from the NATO reporting name attached to the m ...
-A missile *163 km – length of the
Suez Canal The Suez Canal ( arz, قَنَاةُ ٱلسُّوَيْسِ, ') is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia. The long canal is a popular ...
*164 km – length of the
Danyang–Kunshan Grand Bridge The Danyang–Kunshan Grand Bridge () is a viaduct on the Beijing–Shanghai High-Speed Railway. It is the longest bridge in the world. Bridge The bridge is located on the rail line between Shanghai and Nanjing in Jiangsu province. It is in ...
*213 km – length of
Paris Métro The Paris Métro (french: Métro de Paris ; short for Métropolitain ) is a rapid transit system in the Paris metropolitan area, France. A symbol of the city, it is known for its density within the capital's territorial limits, uniform architec ...
*217 km – length of the
Grand Union Canal The Grand Union Canal in England is part of the British canal system. It is the principal navigable waterway between London and the Midlands. Starting in London, one arm runs to Leicester and another ends in Birmingham, with the latter s ...
*223 km – length of the
Madrid Metro The Madrid Metro ( Spanish: ''Metro de Madrid'') is a rapid transit system serving the city of Madrid, capital of Spain. The system is the 14th longest rapid transit system in the world, with a total length of 293 km (182 mi). Its gr ...
*300 km – range of a Scud-B missile *386 km – altitude of the
International Space Station The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ( ...
*408 km – length of the
London Underground The London Underground (also known simply as the Underground or by its nickname the Tube) is a rapid transit system serving Greater London and some parts of the adjacent counties of Buckinghamshire, Essex and Hertfordshire in England. The Un ...
(active track) *460 km – distance from
London London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major s ...
to
Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...
*470 km – distance from Dublin to
London London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major s ...
as the crow flies *600 km – range of a Scud-C missile *600 km – height above ground of the Hubble Space Telescope *804.67 km – (500 miles) distance of the Indy 500 automobile race


Geographical

*111 km – distance covered by one degree of
latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north ...
on Earth's surface *180 km – distance between Mumbai and Nashik *203 km – length of Sognefjorden, the third-largest fjord in the world *220 km – distance between Pune and Nashik *240 km – widest width of the
English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" ( Cotentinais) or (Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...
*430 km – length of the Pyrenees *500 km – widest width of Geography of Sweden, Sweden from east to west *550 km – distance from San Francisco to Los Angeles as the crow flies *560 km – distance of Bordeaux–Paris, formerly the longest one-day professional cycling race *590 km – length of land boundary between Geography of Finland, Finland and Geography of Sweden, Sweden *724 km – length of the Om River *871 km – distance from Sydney to Melbourne (along the Hume Highway) *897 km – length of the River Douro *900 km – distance from Berlin to Stockholm *956 km – distance from Washington, D.C. to Chicago, Illinois as the crow flies


Astronomical

*100 km – the altitude at which the FAI defines
spaceflight Spaceflight (or space flight) is an application of astronautics to fly spacecraft into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in ...
to begin *167 km – diameter of Amalthea (moon), Amalthea, one of
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
's inner moons *200 km – width of Valles Marineris *220 km – diameter of Phoebe (moon), Phoebe, the largest of
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
's outer moons *300 km – the approximate distance travelled by light in one millisecond *340 km – diameter of Nereid (moon), Nereid, the third-largest moon of
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
*350 km – lower bound of Low Earth orbit *420 km – diameter of Proteus (moon), Proteus, the second-largest moon of Neptune *468 km – diameter of the asteroid 4 Vesta *472 km – diameter of Miranda (moon), Miranda, one of Uranus's major moons *974.6 km – greatest diameter of Ceres (dwarf planet), 1 Ceres, the largest Solar System asteroid


1 megametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to  
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (106 m). To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s starting at 106 m (#1 megametre, 1 Mm or 1,000 kilometre, km).


Conversions

1 megametre is equal to: *1 E+6 m (one million metres) *approximately 621.37
mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Englis ...
s *Side of
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
with area 1,000,000 km2


Human-defined scales and structures

*2.100 Mm – Length of proposed Iran-Pakistan-India gas pipeline, gas pipeline from Iran to India via Pakistan *2.100 Mm – Distance from Casablanca to Rome *2.288 Mm – Length of the official Alaska Highway when it was built in the 1940s *3.069 Mm – Length of Interstate 95 (from Houlton, Maine to Miami, Florida) *3.846 Mm – Length of U.S. Route 1 (from Fort Kent, Maine to Key West, Florida) *5.000 Mm – Width of the United States *5.007 Mm – Estimated length of Interstate 90 (Seattle, Washington to Boston, Massachusetts) *5.614 Mm – Length of the Australian Dingo Fence *6.371 Mm – Global-average Earth radius *6.4 Mm – Length of the Great Wall of China *7.821 Mm – Length of the Trans-Canada Highway, the world's longest national highway (from Victoria, British Columbia to St. John's, Newfoundland) *8.836 Mm – Road distance between Prudhoe Bay, Alaska, and Key West, Florida, the endpoints of the U.S. road network *8.852 Mm – Aggregate length of the Great Wall of China, including trenches, hills and rivers *9.259 Mm – Length of the Trans-Siberian railway


Sports

*The Munda Biddi Trail in Western Australia, WA, Australia is over 1,000 km long – the world's longest off-road cycle trail *1.200 Mm – the length of the Paris–Brest–Paris bicycling event *Several endurance auto races are, or were, run for 1,000 km: **Bathurst 1000 **1000 km Brands Hatch **1000 km Buenos Aires **1000 km Donington **1000 km Monza **1000 km Nürburgring **1000 km Silverstone **1000 km Spa **1000 km Suzuka **1000 km Zeltweg


Geographical

*1.010 Mm – Distance from San Diego to El Paso as the crow flies *2.000 Mm – Distance from Beijing to Hong Kong as the crow flies *2.800 Mm – Narrowest width of Atlantic Ocean (Brazil-West Africa) *2.850 Mm – Length of the Danube river *2.205 Mm – Length of Geography of Sweden, Sweden's total land boundaries *2.515 Mm – Length of Geography of Norway, Norway's total land boundaries *3.690 Mm – Length of the Volga river, longest in Europe *4.350 Mm – Length of the Yellow River *4.800 Mm – Widest width of Atlantic Ocean (U.S.-Northern Africa) *5.100 Mm – Distance from Dublin to New York City, New York as the crow flies *6.270 Mm – Length of the Mississippi River, Mississippi-Missouri River system *6.380 Mm – Length of the Yangtze River *6.400 Mm – Length of the Amazon River *6.758 Mm – Length of the Nile River, Nile system, longest on
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
*8.200 Mm – Approximate Distance from Dublin to San Francisco


Astronomical

*1.000 Mm – Estimated shortest axis of Ellipsoid, triaxial dwarf planet *1.186 Mm – Diameter of Charon (moon), Charon, the largest moon of Pluto *1.280 Mm – Diameter of the trans-Neptunian object 50000 Quaoar *1.436 Mm – Diameter of Iapetus (moon), Iapetus, one of
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
's major moons *1.578 Mm – Diameter of Titania (moon), Titania, the largest of Uranus's moons *1.960 Mm – Estimated longest axis of Haumea (dwarf planet), Haumea *2.326 Mm – Diameter of the dwarf planet Eris (dwarf planet), Eris, the largest trans-Neptunian object found to date *2.376 Mm – Diameter of Pluto *2.707 Mm – Diameter of Triton (moon), Triton, largest moon of
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
*3.122 Mm – Diameter of Europa (moon), Europa, the smallest Galilean satellite of
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
*3.476 Mm – Diameter of
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
's Moon *3.643 Mm – Diameter of Io (moon), Io, a moon of Jupiter *4.821 Mm – Diameter of Callisto (moon), Callisto, a moon of Jupiter *4.879 Mm – Diameter of Mercury (planet), Mercury *5.150 Mm – Diameter of Titan (moon), Titan, the largest moon of Saturn *5.262 Mm – Diameter of Jupiter's moon Ganymede (moon), Ganymede, the largest moon in the
Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...
*6.371 Mm – Earth radius, Radius of Earth *6.792 Mm – Diameter of
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...


10 megametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s starting at 107
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (#10 megametre, 10 megametres or 10,000
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s).


Conversions

10 megametres (10 Mm) is *6,215
mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Englis ...
s *side of a
square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length ad ...
of area 100,000,000 square kilometres (km2) *radius of a
circle A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. Equivalently, it is the curve traced out by a point that moves in a plane so that its distance from a given point is con ...
of area 314,159,265 km2


Human-defined scales and structures

*11.085 Mm – Length of the Kyiv-Vladivostok railway, a longer variant of the Trans-Siberian railway *13.300 Mm – Length of roads rehabilitated and widened under the National Highway Development Project (launched in 1998) in India *39.000 Mm – Length of the SEA-ME-WE 3 optical submarine telecommunications cable, joining 39 points between Norden, Lower Saxony, Norden, Germany and Okinawa, Japan *67.000 Mm – Total length of National highways of India, National Highways in India *80.000 Mm – 20,000 (metric, French) league (unit), leagues (see Jules Verne, ''Twenty Thousand Leagues Under the Sea'')


Geographical

*10 Mm – Approximate altitude of the outer boundary of the exosphere *10.001 Mm – Length of the meridian arc from the North Pole to the Equator (the original definition of the
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
was based on this length) *60.000 Mm – Total length of the mid-ocean ridges


Astronomical

*12.000 Mm – Diameter of Sirius, Sirius B, a
white dwarf A white dwarf is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to the Sun's, while its volume is comparable to the Earth's. A white dwarf's faint luminosity comes f ...
*12.104 Mm – Diameter of Venus *12.742 Mm – Diameter of
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
*12.900 Mm – Minimum distance of the meteoroid from the centre of Earth on 31 March 2004, closest on record *14.000 Mm – Smallest diameter of Jupiter's Great Red Spot *19.000 Mm – Separation between Pluto and Charon (moon), Charon *30.8568 Mm – 1 nanoparsec *34.770 Mm – Minimum distance of the asteroid
99942 Apophis 99942 Apophis is a near-Earth asteroid and potentially hazardous asteroid with a diameter of that caused a brief period of concern in December 2004 when initial observations indicated a probability up to 2.7% that it would hit Earth on April&nbs ...
on 13 April 2029 from the centre of Earth *35.786 Mm – Altitude of geostationary orbit *40.005 Mm – Polar circumference of the Earth *40.077 Mm – Equatorial circumference of the Earth *49.528 Mm – Diameter of
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
*51.118 Mm – Diameter of Uranus


100 megametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
s starting at 108
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (#100 megametre, 100 megametres or 100,000
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s or 62,150
mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Englis ...
s). *102 Mm – Diameter of HD 149026 b, an unusually dense gas giant, Jovian planet *115 Mm – Width of Saturn's Rings *120 Mm – Diameter of EBLM J0555-57Ab, the smallest-known star *120 Mm – Diameter of
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
*142 Mm – Diameter of
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
, the largest planet in the
Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...
*170 Mm – Diameter of TRAPPIST-1, a star recently discovered to have seven planets around it *174 Mm – Diameter of OGLE-TR-122b *180 Mm – Average distance covered during life *196 Mm – Diameter of Proxima Centauri, a typical red dwarf *257 Mm – Diameter of TrES-4 b *272 Mm – Diameter of WASP-12b *299.792 Mm – One light-second; the distance light travels in vacuum in one second (see speed of light) *300 Mm – Diameter of WASP-79b *314 Mm – Diameter of CT Cha b *384.4 Mm (238,855 mi) – Average Lunar distance (astronomy), Earth-Moon distance *671 Mm – Separation between
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
and Europa (moon), Europa *428 Mm – Diameter of GQ Lupi b, one of the list of largest exoplanets, largest-known planets *986 Mm – Diameter of HD 100546 b's surrounding disk


1 gigametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to  
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (109 m). To help compare different distances this section lists lengths starting at 109
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (1 gigametre (Gm) or 1 billion
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s). *1.2 Gm – Separation between
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
and Titan (moon), Titan *1.39 Gm – Diameter of Sun *1.5 Gm – ''(proposed) Expected orbit from Earth of the James Webb Space Telescope'' *2.19 Gm – Closest approach of Comet Lexell to
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
, happened on 1 July 1770; closest comet approach on record *3 Gm – Total length of "wiring" in the human brain *4.2 Gm – Diameter of Algol B *5.0 Gm – Closest approach of Comet Halley to Earth, happened on 10 April 837 *5.0 Gm – ''(proposed) Size of the arms of the giant triangle shaped Michelson interferometer of the Laser Interferometer Space Antenna (LISA) planned to start observations sometime in the 2030s.'' *7.9 Gm – Diameter of Bellatrix, Gamma Orionis *9.0 Gm – Estimated diameter of the event horizon of Sagittarius A*, the supermassive black hole in the center of the Milky Way galaxy


10 gigametres

To help compare different distances this section lists lengths starting at 1010
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (10 1 gigametre, gigametres (Gm) or 10 million
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s, or 0.07 astronomical units). *15 Gm – Closest distance of Comet Hyakutake from
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
*18 Gm – One light-minute (see yellow sphere in right-hand diagram) *24 Gm – Radius of a heliostationary orbit *30.8568 Gm – 1 microparsec *46 Gm – Apsis, Perihelion distance of Mercury (planet), Mercury (yellow ellipse on the right) *55 Gm – 60,000-year perigee of
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...
(last achieved on 27 August 2003) *55 Gm – Radius of Rigel, a blue supergiant star (largest star on right) *58 Gm – Average passing distance between
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
and Mars at the moment they overtake each other in their orbits *61 Gm They derived an angular diameter of 20.58±0.03 milliarcsec, which given a distance of 65 light-years yields a diameter of 61 million km. – Diameter of Aldebaran, an red giant, orange giant star (large star on right) *70 Gm – Apsis, Aphelion distance of Mercury *76 Gm – Neso (moon), Neso's apsis, apocentric distance; greatest distance of a natural satellite from its parent planet (
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
)


100 gigametres

To help compare distances at different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
this section lists lengths starting at 1011
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (100 Orders of magnitude (length)#1 gigametre, gigametre or 100 million
kilometre The kilometre ( SI symbol: km; or ), spelt kilometer in American English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is now the measurement unit used for ex ...
s or 0.7 astronomical units). *109 Gm (0.7 au) Distance between Venus and the Sun *149.6 Gm (93.0 million mi; 1.0 au) – Distance between the
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
and the Sun – the original definition of the astronomical unit *180 Gm (1.2 au) – Maximum diameter of Sagittarius A*, the supermassive black hole in the center of Milky Way galaxy *228 Gm (1.5 au) – Distance between
Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin atmosp ...
and the Sun *570 Gm (3.8 au) – Length of the tail of Comet Hyakutake measured by ''Ulysses (spacecraft), Ulysses''; the actual value could be much higher *591 Gm (4.0 au) – Minimum distance between the
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
and
Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth th ...
*780 Gm (5.2 au) – Distance between Jupiter and the Sun *947 Gm (6.4 au) – Diameter of Antares, Antares A *965 Gm (6.4 au) – Maximum distance between the Earth and Jupiter


1 terametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to  
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s (1012 m). To help compare different distances, this section lists lengths starting at 1012 m (1 #1 terametre, Tm or 1 billion kilometre, km or 6.7 astronomical units). *1.079 Tm – 7.2 au – One light-hour *1.4 Tm – 9.5 au – Distance between
Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...
and the Sun *1.5 Tm – 10 au – Estimated diameter of VV Cephei A, a red supergiant. *1.83 Tm – 12.2 au – Diameter of HR 5171 A, the largest-known yellow hypergiant star although the latest research suggests it is a red hypergiant with a diameter about 2.1 Tm (14 au) *2 Tm – 13.2 au – Estimated diameter of VY Canis Majoris, one of the list of largest stars, largest-known stars *2.9 Tm – 19.4 au – Distance between Uranus and the Sun *4.4 Tm – 29.4 au – Apsis, Perihelion distance of Pluto *4.5 Tm – 30.1 au – Distance between
Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
and the Sun *4.5 Tm – 30.1 au – Inner radius of the Kuiper belt *5.7 Tm – 38.1 au – Perihelion distance of 136199 Eris, Eris *7.3 Tm – 48.8 au – Apsis, Aphelion distance of Pluto *7.5 Tm – 50.1 au – Outer radius of the Kuiper Belt


10 terametres

To help compare different distances this section lists lengths starting at 1013 m (10 #1 terametre, Tm or 10 billion kilometre, km or 67 astronomical units). *10 Tm – 67 AU – Diameter of a hypothetical quasi-star *11.1 Tm – 74.2 AU – Distance that ''Voyager 1'' began detecting returning particles from termination shock *11.4 Tm – 76.2 AU – Apsis, Perihelion distance of 90377 Sedna *12.1 Tm – 70 to 90 AU – Distance to termination shock (''Voyager 1'' crossed at 94 AU) *12.9 Tm – 86.3 AU – Distance to 90377 Sedna in March 2014 *13.2 Tm – 88.6 AU – Distance to ''Pioneer 11'' in March 2014 *14.1 Tm – 94.3 AU – Estimated radius of the
Solar System The Solar System Capitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar ...
*14.4 Tm – 96.4 AU – Distance to 136199 Eris, Eris in March 2014 (now near its apsis, aphelion) *15.1 Tm – 101 AU – Distance to Heliosphere#Heliosheath, heliosheath *16.5 Tm – 111 AU – Distance to ''Pioneer 10'' as of March 2014 *16.6 Tm – 111.2 AU – Distance to ''Voyager 2'' as of May 2016 *20.0 Tm – 135 AU – Distance to ''Voyager 1'' as of May 2016 *20.6 Tm – 138 AU – Distance to ''Voyager 1'' as of late February 2017 *21.1 Tm – 141 AU – Distance to ''Voyager 1'' as of November 2017 *25.9 Tm – 173 AU – One light-day *30.8568 Tm – 1 miliparsec *55.7 Tm – 371 AU – Aphelion distance of the comet Hale-Bopp


100 terametres

To help compare different distances this section lists lengths starting at 1014 m (100 #1 terametre, Tm or 100 billion kilometre, km or 670 astronomical units). *140 Tm – 937 AU – Apsis, Aphelion distance of 90377 Sedna *172 Tm – 1150 AU – Schwarzschild radius, Schwarzschild diameter of H1821+643, one of the most massive black holes known *181 Tm – 1210 AU – One light-week *757 Tm – 5059 AU – radius of the Stingray Nebula *777 Tm – 5180 AU – One light-month


1 petametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 1015 
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s. To help compare different distances this section lists lengths starting at 1015 m (1 Pm or 1 trillion kilometre, km or 6685 astronomical units (AU) or 0.11 light-years). *1.0 Pm = 0.105702341 light-years *1.9 Pm ± 0.5 Pm = 12,000 AU = 0.2 light-year radius of Cat's Eye Nebula's inner coreradius = distance times sin(angular diameter/2) = 0.2 light-year. Distance = 3.3 ± 0.9 light-year, kly; angular diameter = 20 arcseconds *4.7 Pm = 30,000 AU = half-light-year diameter of Bok globule Barnard 68 *7.5 Pm – 50,000 AU – Possible outer boundary of Oort cloud (other estimates are 75,000 to 125,000 or even 189,000 Astronomical unit, AU (1.18, 2, and 3 light-years, respectively)) *9.5 Pm – 63,241.1 AU – One light-year, the distance traveled by light in one year *9.9 Pm – 66,000 AU – Apsis, Aphelion distance of the C/1999 F1 (Catalina)


10 petametres

To help compare different distances this section lists lengths starting at 1016 m (10 #1 petametre, Pm or 66,800 astronomical unit, AU, 1.06 light-years). *15 Pm – 1.59 light-years – Possible outer radius of Oort cloud *20 Pm – 2.11 light-years – maximum extent of influence of the Sun's gravitational field *30.9 Pm – 3.26 light-years – 1
parsec The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (au), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, a ...
*39.9 Pm – 4.22 light-years – Distance to Proxima Centauri (nearest star to Sun) *81.3 Pm – 8.59 light-years – Distance to Sirius


100 petametres

To help compare different distances this section lists lengths between 1017 m (100 #1 petametre, Pm or 11 light-years) and 1018 m (106 light-years). *110 Pm – 12 light-years – Distance to Tau Ceti *230 Pm – 24 light-years – Diameter of the Orion Nebula *240 Pm – 25 light-years – Distance to Vega *260 Pm – 27 light-years – Distance to Beta Canum Venaticorum, Chara, a star approximately as bright as our Sun. Its faintness gives us an idea how our Sun would appear when viewed from even so close a distance as this. *350 Pm – 37 light-years – Distance to Arcturus *373.1 Pm – 39.44 light-years – Distance to TRAPPIST-1, a star recently discovered to have 7 planets around it *400 Pm – 42 light-years – Distance to Capella (star), Capella *620 Pm – 65 light-years – Distance to Aldebaran *750 Pm – 79.36 light-years – Distance to Regulus *900 Pm – 92.73 light-years – Distance to Algol


1 exametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 1018
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s. To help compare different distances this section lists lengths between 1018  m (1 exametre, Em or 105.7 light-years) and 1019 m (10 Em or 1,057 light-years). *1.2 Em – 129 light-years – Diameter of Messier 13 (a typical globular cluster) *1.6 Em – 172 ± 12.5 light-years – Diameter of Omega Centauri (one of the largest-known globular clusters, perhaps containing over a million stars) *3.1 Em – 310 light-years – Distance to Canopus (star), Canopus according to ''Hipparcos''Vizier catalog entry
/ref> * *6.1 Em – 640 light-years – Distance to Betelgeuse according to ''Hipparcos'' *6.2 Em – 650 light-years – Distance to the Helix Nebula, located in the constellation Aquarius (constellation), Aquarius *7.3 Em – 730 light-years – Distance to Rigel according to ''Hipparcos''


10 exametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 10 exametre, Em (1019 m or 1,100 light-years). *10.6 Em – 1,120 light-years – Distance to WASP-96b *13 Em – 1,300 light-years – Distance to the Orion Nebula *14 Em – 1,500 light-years – Approximate thickness of the Galactic plane, plane of the Milky Way galaxy at the Sun's location *14.2 Em – 1,520 light-years – Diameter of the NGC 604 *30.8568 Em – 3,261.6 light-years – 1 parsec, kiloparsec *31 Em – 3,200 light-years – Distance to Deneb according to ''Hipparcos'' *46 Em – 4,900 light-years – Distance to OGLE-TR-56, the first extrasolar planet discovered using the extrasolar planet#Transit method, transit method *47 Em – 5,000 light-years – Distance to the Boomerang nebula, coldest place known (1 E0 K, 1 K) *53 Em – 5,600 light-years – Distance to the globular cluster Messier 4, M4 and the extrasolar planet PSR B1620-26 b within it *61 Em – 6,500 light-years – Distance to Perseus Spiral Arm (next spiral arm out in the Milky Way galaxy) *71 Em – 7,500 light-years – Distance to Eta Carinae


100 exametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 100 exametre, Em (1020 m or 11,000 light-years). *150 Em – 16,000 light-years – Diameter of the Small Magellanic Cloud, a dwarf galaxy orbiting the Milky Way *200 Em – 21,500 light-years – Distance to OGLE-2005-BLG-390Lb, the most distant and the most
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface ...
-like planet known *240 Em – 25,000 light-years – Distance to the Canis Major Dwarf Galaxy *260 Em – 28,000 light-years – Distance to the center of the Milky Way, Galaxy *830 Em – 88,000 light-years – Distance to the Sagittarius Dwarf Elliptical Galaxy


1 zettametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 1021
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s. To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 1 zettametre, Zm (1021  m or 110,000 light-years). *1.7 Zm – 179,000 light-years – Distance to the Large Magellanic Cloud, largest satellite galaxy of the Milky Way *<1.9 Zm – <200,000 light-years – Revised estimated diameter of the disc of the Milky Way, Milky Way Galaxy. The size was previously thought to be half of this. *2.0 Zm – 210,000 light-years – Distance to the Small Magellanic Cloud *2.8 Zm – 300,000 light-years – Distance to the Intergalactic Wanderer, one of the most distant globular clusters of Milky Way *8.5 Zm – 900,000 light-years – Distance to the Leo I Dwarf Galaxy, farthest-known Milky Way satellite galaxy


10 zettametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 10 zettametre, Zm (1022 m or 1.1 million light-years). *24 Zm – 2.5 million light-years – Distance to the Andromeda Galaxy *30.8568 Zm – 3.2616 million light-years – 1 parsec, megaparsec *40 Zm – 4.2 million light-years – Distance to the IC 10, a distant member of the Local Group of galaxy, galaxies *49.2 Zm – 5.2 million light-years – Width of the Local Group of galaxy, galaxies *95 Zm – 10 million light-years – Distance to the Sculptor Galaxy in the Sculptor Group of galaxies *95 Zm – 10 million light-years – Distance to the Maffei 1, the nearest giant elliptical galaxy in the Maffei 1 group of galaxies, Maffei 1 Group


100 zettametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 100 zettametre, Zm (1023 m or 11 million light-years). *140 Zm – 15 million light-years – Distance to Centaurus A galaxy *250 Zm – 27 million light-years – Distance to the Pinwheel Galaxy *280 Zm – 30 million light-years – Distance to the Sombrero Galaxy *570 Zm – 60 million light-years – Approximate distance to the Virgo cluster, nearest galaxy cluster *620 Zm – 65 million light-years – Approximate distance to the Fornax cluster *800 Zm – 85 million light-years – Approximate distance to the Eridanus cluster


1 yottametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 1024 
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s. To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 1 Ym (1024 m or 105.702 million light-years). *1.2 Ym – 127 million light-years – Distance to the closest observed gamma ray burst GRB 980425 *1.3 Ym – 137 million light-years – Distance to the Centaurus Cluster of galaxies, the nearest large supercluster *1.9 Ym – 201 million light-years – Diameter of the Local Supercluster *2.3 Ym – 225 to 250 million light-years – Distance light travels in vacuum in one galactic year *2.8 Ym – 296 million light-years – Distance to the Coma Cluster *3.2 Ym – 338 million light-years – Distance to the Stephan's Quintet *4.7 Ym – 496 million light-years – Length of the Great Wall (astronomy), CfA2 Great Wall, one of the largest observed superstructures in the Universe *6.1 Ym – 645 million light-years – Distance to the Shapley Supercluster *9.5 Ym – 996 million light-years – Diameter of the Eridanus Supervoid


10 yottametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 10 yottametre, Ym (1025 m or 1.1 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depends on the physical cosmology, cosmological models used. *13 Ym – 1.37 billion light-years – Length of the South Pole Wall *13 Ym – 1.38 billion light-years – Length of the Sloan Great Wall *18 Ym – redshift 0.16 – 1.9 billion light-years – Distance to the quasar 3C 273 (distance measures (cosmology)#Types of distance measures, light travel distance) *30.8568 Ym – 3.2616 billion light-years – 1 gigaparsec *31.2204106 Ym − 3.3 billion light-years − Length of The Giant Arc, a large cosmic structure discovered in 2021 *33 Ym – 3.5 billion light-years – Maximum distance of the 2dF Galaxy Redshift Survey (light travel distance) *37.8 Ym – 4 billion light-years – Length of the Huge-LQG *75 Ym – redshift 0.95 – 8 billion light-years – Approximate distance to the supernova SN 2002dd in the Hubble Deep Field North (light travel distance) *85 Ym – redshift 1.6 – 9 billion light-years – Approximate distance to the gamma-ray burst GRB 990123 (light travel distance) *94.6 Ym – 10 billion light-years – Approximate distance to quasar OQ172 *94.6 Ym – 10 billion light-years – Length of the Hercules–Corona Borealis Great Wall, one of the list of largest cosmic structures, largest and most massive-known cosmic structures known


100 yottametres

To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 100 yottametre, Ym (1026 m or 11 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the physical cosmology, cosmological models used. *124 Ym – redshift 7.54 – 13.1 billion light-years – Distance measures (cosmology)#Types of distance measures, Light travel distance (LTD) to the quasar ULAS J1342+0928, the List of quasars#Most distant quasars, most distant-known quasar as of 2017 *130 Ym – redshift 1,000 – 13.8 billion light-years – Distance (LTD) to the source of the Cosmic microwave background, cosmic microwave background radiation; radius of the observable universe measured as a LTD *260 Ym – 27.4 billion light-years – Diameter of the observable universe (double LTD) *440 Ym – 46 billion light-years – Radius of the universe measured as a comoving distance *590 Ym – 62 billion light-years – Cosmological event horizon: the largest comoving distance from which light will ever reach us (the observer) at any time in the future *886.48 Ym – 93.7 billion light-years – The diameter of the observable universe (twice the particle horizon); however, there might be unobserved distances that are even greater.


1 ronnametre

The ' ( SI symbol: ') is a
unit Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...
of
length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...
in the
metric system The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the Internati ...
equal to 1027 
metre The metre ( British spelling) or meter ( American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pre ...
s. To help compare different
orders of magnitude An order of magnitude is an approximation of the logarithm of a value relative to some contextually understood reference value, usually 10, interpreted as the base of the logarithm and the representative of values of magnitude one. Logarithmic dis ...
, this section lists distances starting at 1 Rm (1027 m or 110 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the physical cosmology, cosmological models used. *>1 Rm - >105.7 billion light-years – Size of universe beyond the observable universe, cosmic light horizon, depending on its curvature; if the curvature is zero (i.e. the universe is spatially flat), the value can be infinity#Infinity in cosmology, infinite (see Shape of the universe) as previously mentioned


See also

*List of examples of lengths *Fermi problem *Scale (analytical tool) *Spatial scale


Notes


References


External links


How Big Are Things?
– displays orders of magnitude in successively larger rooms.

– Travel across the Universe.

(Digital Nature Agency).
Scale of the universe
– interactive guide to length magnitudes * �
Orders of Magnitude
(March 2020). {{Portal bar, Physics, Mathematics, Astronomy, Stars, Spaceflight, Outer space, Solar System, Science Orders of magnitude (length), Length Orders of magnitude, Length Lists by length