Megameter

The following are examples of orders of magnitude for different lengths.

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

1 quectometre and less

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
To help compare different orders of magnitude, this section lists lengths shorter than 10⁻³⁰ m (1 qm).
*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.)
*1 qm – 1 quectometre, the smallest named subdivision of the metre in the SI base unit of length, one nonillionth of a metre.

1 rontometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
*1 rm – 1 rontometre, a subdivision of the metre in the SI base unit of length, one octillionth of a metre.

10 rontometres

*10 rm – the length of one side of a square whose area is one List of humorous units of measurement#Barn, outhouse, shed, shed, a unit of Cross section (physics), target cross section used in nuclear physics

1 yoctometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
*2 ym – the effective cross-section radius of 1 MeV neutrinos as measured by Clyde Cowan and Frederick Reines.

1 zeptometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
To help compare different orders of magnitude, this section lists lengths 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 in string theory.
*2 zm – radius of effective Cross section (physics), cross section for a orders of magnitude (energy)#1E-9, 20 GeV neutrino scattering off a nucleon
*7 zm – radius of effective cross section for a orders of magnitude (energy)#1E-9, 250 GeV neutrino scattering off a nucleon

10 zeptometres

To help compare different orders of magnitude, this section lists lengths between 10⁻²⁰ m and 10⁻¹⁹ m (10 Zeptometre, zm and 100 zm).

100 zeptometres

To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁹ m and 10⁻¹⁸ m (100 zeptometre, zm and 1 Attometre, am).

*177 zm – de Broglie wavelength of protons at the Large Hadron Collider (7 TeV as of 2010)

1 attometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁸ m and 10⁻¹⁷ m (1 am and 10 am).

*1 am – sensitivity of the LIGO detector for gravitational waves
*1 am – upper limit for the size of quarks and electrons

10 attometres

To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁷ m and 10⁻¹⁶ m (10 attometre, am and 100 am).

*10–100 am – range of the weak force
*86 am – charge radius of a Eta meson, Bottom eta meson

100 attometres

To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁶ m and 10⁻¹⁵ m (100 attometre, am and 1 femtometre, fm).

*831 am – approximate proton radius

1 femtometre (or 1 fermi)

The ' ( SI symbol: ') is a unit of length in the metric system equal to .
In particle physics, this unit is sometimes called a fermi (unit), , also with abbreviation "fm". To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁵ metre, metres and 10⁻¹⁴ metres (1 femtometre and 10 fm).

*1 fm – diametre of a neutron, approximate range-limit of the strong interaction, color force carried between quarks by gluons
*1.5 fm – diametre of the cross section (physics), scattering cross section of an 11 electron volt, MeV proton with a target proton
*1.75 fm – the effective charge diametre of a proton
*2.81794 fm – classical electron radius
*3 fm – approximate range-limit of the strong interaction, nuclear binding force mediated by mesons
*7 fm – the radius of the effective scattering cross section for a gold nucleus scattering a orders of magnitude (energy)#1E-15, 6 electron volt, MeV alpha particle over 140 degrees

10 femtometres

To help compare different orders of magnitude, this section lists lengths between 10⁻¹⁴ m and 10⁻¹³ m (10 femtometre, fm and 100 fm).

*1.75 to 15 fm – diametre range of the atomic nucleus
*10 fm – the length of one side of a square whose area is one barn (unit), barn (10⁻²⁸ m²), a unit of Cross section (physics), target cross section used in nuclear physics
*30.8568 fm – 1 quectoparsec (10⁻³⁰ parsecs)

100 femtometres

To help compare different orders of magnitude, this section lists lengths between 10⁻¹³ m and 10⁻¹² m (100 femtometre, fm and 1 picometre, pm).

*570 fm – typical distance from the atomic nucleus of the two innermost electrons (electrons in the ''1s'' shell) in the uranium atom, the heaviest naturally-occurring atom

1 picometre

The ' ( SI symbol: ''pm'') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude this section lists lengths between 10⁻¹² and 10⁻¹¹ m (1 pm and 10 pm).

*1 pm – distance between atomic nuclei in a white dwarf
*1 pm – reference value of particle displacement in acoustics
*2.4 pm – the Compton wavelength of an electron
*5 pm – shorter X-ray wavelengths (approx.)

10 picometres

To help compare different orders of magnitude this section lists lengths between 10⁻¹¹ and 10⁻¹⁰ m (10 pm and 100 pm).

*25 pm – approximate radius of a helium atom, the smallest neutral atom
*30.8568 pm – 1 rontoparsec
*50 pm – radius of a hydrogen atom
*50 pm – bohr radius: approximate radius of a hydrogen atom
*~50 pm – best resolution of a high-resolution transmission electron microscopy, high-resolution transmission electron microscope
*60 pm – radius of a carbon atom
*93 pm – length of a diatomic carbon molecule
*96 pm – H–O bond length in a water molecule

100 picometres

To help compare different orders of magnitude this section lists lengths between 10⁻¹⁰ and 10⁻⁹ m (100 pm and 1 nm; 1 angstrom, Å and 10 Å).

*100 pm – 1 ångström
*100 pm – covalent radius of sulfur atom
*120 pm – van der Waals radius of a neutral hydrogen atom
*120 pm – radius of a gold atom
*126 pm – covalent radius of ruthenium atom
*135 pm – covalent radius of technetium atom
*150 pm – length of a typical covalent bond (Carbon, C–C)
*153 pm – covalent radius of silver atom
*155 pm – covalent radius of zirconium atom
*175 pm – covalent radius of thulium atom
*200 pm – highest resolution of a typical electron microscope
*225 pm – covalent radius of caesium atom
*280 pm – average size of the water molecule
*298 pm – radius of a caesium atom, atomic radius#Calculated atomic radii, calculated to be the largest atomic radius
*340 pm – thickness of single layer graphene
*356.68 pm – width of diamond unit cell
*403 pm – width of lithium fluoride unit cell
*500 pm – Width of protein alpha helix, α helix
*543 pm – silicon lattice spacing
*560 pm – width of sodium chloride unit cell
*700 pm – width of glucose molecule
*700 pm – diametre of a buckyball
*780 pm – mean width of quartz unit cell
*820 pm – mean width of ice unit cell
*900 pm – mean width of coesite unit cell

1 nanometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude, this section lists lengths between 10⁻⁹ and 10⁻⁸ m (1 nm and 10 nm).

*1 nm – diametre of a carbon nanotube
*1 nm – roughly the length of a sucrose molecule, calculated by Albert Einstein
*2.3 nm – length of a phospholipid
*2.3 nm – smallest Gate (transistor), gate oxide thickness in microprocessors
*3 nm – width of a DNA helix
*3 nm – flying height of the disk read-and-write head, head of a hard disk
*3 nm – the 3 nm process, average half-pitch of a memory cell manufactured circa 2022
*3.4 nm – length of a DNA turn (biochemistry), turn (10 base pair, bp)
*3.8 nm – size of an albumin molecule
*5 nm – size of the gate length of a 16 nm processor
*5 nm – the 5 nm process, average half-pitch of a memory cell manufactured circa 2019–2020
*6 nm – length of a phospholipid bilayer
*6–10 nm – thickness of cell membrane
*6.8 nm – width of a haemoglobin molecule
*7 nm – diametre of Microfilament, actin filaments
*7 nm – the 7 nm process, average half-pitch of a memory cell manufactured circa 2018
*10 nm – thickness of cell wall in Gram staining, Gram-negative bacteria

10 nanometres

To help compare different orders of magnitude this section lists lengths between 10⁻⁸ and 10⁻⁷ m (10 nm and 100 nm).

*10 nm Shortest extreme ultraviolet wavelength or longest X-ray wavelengthIntroduction to the Electromagnetic Spectrum and Spectroscopy
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*10 nm – the average length of a nanowire
*10 nm – lower size of tobacco smokeAnnis, Patty J. October 1991. Kansas State University. ''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 10 nm process, average half-pitch of a memory cell manufactured circa 2016 32 nm process, –2017
*13 nm – the length of the wavelength that is used for EUV lithography
*14 nm – length of a porcine circovirus
*14 nm – the 14 nm process, average half-pitch of a memory cell manufactured circa 2013
*15 nm – length of an antibody
*18 nm – diametre of tobacco mosaic virus
*20 nm – length of a nanobe, could be one of the smallest forms of life
*20–80 nm – thickness of cell wall in Gram-positive bacteria
*20 nm – thickness of bacterial flagellum
*22 nm – the 22 nm process, average half-pitch of a memory cell manufactured circa 2011–2012
*22 nm – smallest feature size of production microprocessors in September 2009
*25 nm – diametre of a microtubule
*30 nm – lower size of cooking oil smoke
*30.8568 nm – 1 yoctoparsec
*32 nm – the 32 nm process, average half-pitch of a memory cell manufactured circa 2009–2010
*40 nm – extreme ultraviolet wavelength
*45 nm – the 45 nm process, average half-pitch of a memory cell manufactured circa 2007–2008
*50 nm – upper size for airborne virus particles
*50 nm – flying height of the disk read-and-write head, head of a hard disk
*65 nm – the 65 nm process, average half-pitch of a memory cell manufactured circa 2005–2006
*58 nm – height of a T7 bacteriophage
*90 nm – HIV/AIDS, human immunodeficiency virus (HIV) (generally, viruses range in size from 20 nm to 450 nm)
*90 nm – the 90 nm process, average half-pitch of a memory cell manufactured circa 2002–2003
*100 nm – Length of a mesoporous silica nanoparticle

100 nanometres

To help compare different orders of magnitude, this section lists lengths between 10⁻⁷ and 10⁻⁶ m (100 nanometre, nm and 1 micrometre, μm).

*100 nm – greatest particle size that can fit through a surgical mask
*100 nm – 90% of particles in wood smoke are smaller than this.
*120 nm – greatest particle size that can fit through a ULPA filter
*120 nm – diametre of a human immunodeficiency virus (HIV)
*120 nm – approximate diametre of Severe acute respiratory syndrome coronavirus 2, SARS-CoV-2
*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, rabies virus
*200 nm – typical size of a ''Mycoplasma'' bacterium, among the smallest bacteria
*300 nm – greatest particle size that can fit through a HEPA (high efficiency particulate air) filter (N100 removes up to 99.97% at 300 nm, N95 removes up to 95% at 300 nm)
*300–400 nm – near ultraviolet wavelength
*400–420 nm – wavelength of violet (color), violet light (see Color and Visible spectrum)
*420–440 nm – wavelength of indigo light
*440–500 nm – wavelength of blue light
*500–520 nm – wavelength of cyan light
*520–565 nm – wavelength of green light
*565–590 nm – wavelength of yellow light
*590–625 nm – wavelength of orange (colour), orange light
*625–700 nm – wavelength of red light
*700–1.4 μm – wavelength of near-infrared radiation

1 micrometre (or 1 micron)

The ' ( SI symbol: ') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude, this section lists some items with lengths between 10⁻⁶ and 10⁻⁵ m (between 1 and 10 micrometre, micrometres, or μm).

*~0.7–300 μm – wavelength of infrared radiation
*1 μm – the side of a square (geometry), square of area orders of magnitude (area), 10⁻¹² m²
*1 μm – edge of cube (geometry), cube of volume orders of magnitude (volume), 10⁻¹⁸ m³ (1 fL)
*1–10 μm – diametre of a typical bacterium
*1 μm – length of a lysosome
*1–2 μm – anthrax disease, anthrax spore
*2 μm – length of an average E. coli bacteria
*3–4 μm – size of a typical yeast cell
*5 μm – length of a typical human spermatozoon's head
*6 μm – thickness of the tape in a 120-minute (C120) compact cassette
*7 μm – diametre of the cell nucleus, nucleus of a typical eukaryotic cell (biology), cell
*about 7 μm – diametre of human red blood cells
*3–8 μm – width of strand of spider silk, spider web silk
*5–10 μm – width of a chloroplast
*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
*7–12 μm – the diametre of human white blood cells
*8–10 μm – the diametre of human macrophages

10 micrometres

To help compare different orders of magnitude, this section lists lengths between 10⁻⁵ m and 10⁻⁴ m (10 micrometre, μm and 100 μm).

*10 μm – width of cotton fibre
*10 μm – Engineering tolerance, tolerance of a Lego brick
*10 μm – transistor width of the Intel 4004, the world's first commercial microprocessor
*10 μm – mean longest dimension of a human red blood cell
*5–20 μm – dust mite excreta
*10.6 μm – wavelength of light emitted by a carbon dioxide laser
*15 μm – width of silk 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 fibre
*25.4 μm – 1/1,000 inch, commonly referred to as 1 thou (unit of length), mil in the U.S. and 1 thou (unit of length), thou in the U.K.
*30 μm – length of a human skin cell
*30.8568 μm – 1 zeptoparsec
*50 μm – typical length of ''Euglena gracilis'', a flagellate protist
*50 μm – typical length of a human liver cell, an average-sized body cell
*50 μm – length of a silt particle
*60 μm – length of a sperm cell
*78 μm — width of a pixel on the display of the iPhone 4, marketed as Retina Display
*70 to 180 μm – thickness of paper

100 micrometres

To help compare different orders of magnitude, this section lists lengths between 10⁻⁴ m and 10⁻³ m (100 micrometre, μm and 1 millimetre, mm). The term ''myriometre'' (abbr. mom, equivalent to 100 micrometres; frequently confused with the ''#Myriametre, myriametre'', 10 kilometres) is deprecated; the decimal metric prefix myria-, myrio- is obsolete and was not included among the SI prefixes, prefixes when the International System of Units 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
*100 μm – average diametre of a strand of human hair
*100 μm – thickness of a coat of paint
*100 μm – length of a dust particle
*120 μm – the geometric mean of the Planck length and the diametre of the observable universe:
*120 μm – diametre of a human ovum
*170 μm – length of the largest mammalian sperm cell (rat)
*170 μm – length of the largest sperm cell 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 follicles
*175–200 μm – typical thickness of a solar cell.
*200 μm – typical length of ''Paramecium, 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
*340 μm – length of a pixel on a 17-inch monitor with a resolution of 1024×768
*500 μm – typical length of ''Amoeba proteus'', an amoeboid protist
*500 μm – Microelectromechanical systems, MEMS micro-engine
*500 μm – average length of a grain of sand
*500 μm – average length of a grain of salt
*500 μm – average length of a grain of sugar
*560 μm – thickness of the central area of a human cornea
*750 μm – diametre of a Thiomargarita namibiensis, the largest bacteria known
*760 μm – thickness of an ISO/IEC 7810, identification card

1 millimetre

The ' ( SI symbol: ') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude, 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 inches or 5/127 (exactly)
*1.0 mm – side of a square (geometry), square of area 1 E-6 m², 1 mm²
*1.0 mm – diametre of a pinhead
*1.5 mm – average length of a flea
*2.54 mm – distance between pins on old dual in-line package (DIP) electronic components
*5 mm – length of an average red ant
*5 mm – diametre of an average grain of rice
*5.56×45mm NATO – standard ammunition size
*6 mm – approximate width of a pencil
*7 mm – length of a ''Paedophryne amauensis'', the smallest-known vertebrate
*7.1 mm – length of a sunflower seed
*7.62×51mm NATO – common military ammunition size
*8 mm – width of old-format home movie film
*8 mm – length of a ''Paedocypris progenetica'', the smallest-known fish

1 centimetre

The ' ( SI symbol: ') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude, this section lists lengths between 10⁻² m and 10⁻¹ m (1 cm and 1 dm).

*1 cm – 10 millimetres, millimetres
*1 cm – 0.39 inches
*1 cm – edge of a square of area orders of magnitude (area), 1 cm²
*1 cm – edge of a cube (geometry), cube of volume orders of magnitude (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 – diametre 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
*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 diametre of a golf ball
*5 cm – usual diametre of a chicken egg
*5 cm – height of a hummingbird, the smallest-known bird
*5.08 cm – 2 inches,
*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 – diametre of a baseball
*8.6 cm × 5.4 cm – dimensions of a standard credit card (also called CR80)
*9 cm – length of a speckled padloper, the smallest-known turtle

1 decimetre

The ' ( SI symbol: ') is a unit of length in the metric system equal to ().
To help compare different orders of magnitude, this section lists lengths between 10 centimetre, centimetres and 100 centimetres (10⁻¹ metre and 1 metre).

Conversions

10 centimetres (abbreviated to 10 cm) is equal to:

*1 decimetre, decimetre (dm), a term not in common use (1 litre, L = 1 dm³.)
*100 millimetre, millimetres
*3.9 inches
*a side of a square (geometry), square of area orders of magnitude (area), 0.01 m²
*the edge of a cube (geometry), cube with a volume of orders of magnitude (one cubic millimetre to one cubic metre), m³ (1 L)

Wavelengths

*10 cm = 1.0 dm – wavelength of the highest ultra high frequency, UHF radio frequency, picosecond, 3 GHz
*12 cm = 1.2 dm – wavelength of the ISM band, 2.45 GHz ISM radio band
*21 cm = 2.1 dm – wavelength of the 21 cm line, 1.4 GHz hydrogen emission line, a hyperfine structure, hyperfine transition of the hydrogen atom
*100 cm = 10 dm – wavelength of the lowest UHF radio frequency, nanosecond, 300 MHz

Human-defined scales and structures

*10.16 cm = 1.016 dm – 1 hand (unit), hand used in measuring height of horses (4 inches)
*12 cm = 1.2 dm – diametre of a compact disc (CD) (= 120 mm)
*15 cm = 1.5 dm – length of a Bic Cristal, Bic pen with cap on
*22 cm = 2.2 dm – diametre 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 (length), foot (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 – diametre of the human cervix upon entering the second stage of labour
*11 cm = 1.1 dm – length of an average potato in the U.S.
*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
*30 cm = 3.0 dm – maximum leg length of a Goliath birdeater
*31 cm = 3.1 dm – wingspan of largest butterfly species Queen Alexandra's birdwing, ''Ornithoptera alexandrae''
*32 cm – length of the Goliath frog, the world's largest frog
*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 diametre of 2008 TS26, a meteoroid

1 metre

To help compare different orders of magnitude, this section lists lengths between one metre, metre and ten metres.
Light, in vacuum, travels 1 metre in , or of a second.

Conversions

1 metre, metre is:
*10 decimetre, decimetres
*100 centimetre, centimetres
*1,000 millimetre, millimetres
*39.37 inches
*3.28 foot (length), feet
*1.1 yards
*side of square (geometry), square with area 1 E0 m², 1 m²
*edge of cube (geometry), cube with surface area 1 E0 m², 6 m² and volume 1 E0 m³, 1 m³
*radius of circle with area 1 E0 m², π m²
*radius of sphere with surface area 1 E+1 m², 4π m² and volume 1 E0 m³, 4/3π m³

Human-defined scales and structures

*1 m – approximate height of the top part of a doorknob on a door
*1 m – diametre of a very large beach ball
*1 m - height of a typical washing machine
*1.29 m – length of the Cross Island Chapel, the smallest church in the world
*1.4 m – length of a Peel P50, the world's smallest car
*1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 8 in
*2 m - typical height of an average door
*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 m – length of the Tsar Bomba, the largest bomb ever detonated
*8.38 m – the length of a London Bus (AEC Routemaster)

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 – length of ''Rafflesia arnoldii'', the largest flower in the world
*1 m – height of ''Homo floresiensis'' (the "Hobbit")

*1.15 m – a pizote (mammal)
*1.5 m – height of an okapi
*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)
*2.4 m – wingspan of a mute swan
*2.5 m – height of a sunflower
*2.7 m – length of a leatherback sea turtle, the largest living turtle
*2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow)
*3 m – length of a giant Gippsland earthworm
*3 m – length of an Komodo dragon, the largest living lizard
*3.63 m – the record wingspan for living birds (a wandering albatross)
*3.7 m – leg span of a Japanese spider crab
*3.7 m – length of a southern elephant seal, the largest living pinniped
*5 m – length of an elephant
*5.2 m – height of a giraffe
*5.5 m – height of a ''Baluchitherium'', the largest land mammal ever lived
*6.5 m – wingspan of ''Argentavis'', the largest flying bird known
*6.7 m – length of a ''Microchaetus rappi''
*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 diametre of , a meteoroid
*4.1 m – diametre of 2008 TC3, a small asteroid that flew into the Earth's atmosphere on 7 October 2008

1 decametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to 10 metre, metres (10¹ m).
To help compare different orders of magnitude, this section lists lengths between 10 and 100 metres.

Conversions

10 metres (very rarely termed a decametre, decametre which is abbreviated as dam) is equal to:
*10 metres
*100 decimetre, decimetres
*1,000 centimetre, centimetres
*10,000 millimetre, millimetres
* 10,000,000 micrometre, micrometres (or rarely 10,000,000 microns)
*32.8 foot (length), feet
*11 yards
*side of a square (geometry), square with area 1 E+2 m², 100 m²

Human-defined scales and structures

*10 metres – wavelength of the highest shortwave radio frequency, 1 E7 Hz, 30 Mhertz, Hz
*10.2 metres – length of the Panzer VIII Maus, the world's largest tank
*12 metres – height of the Newby-McMahon Building, the world's littlest skyscraper
*23 metres – height of Luxor Obelisk, located in the Place de la Concorde, Paris, France
*25 metres – wavelength of the broadcast radio shortwave band at 1 E7 Hz, 12 MHz
*29 metres – height of the Savudrija Lighthouse
*30 metres – height of Christ the Redeemer (statue), Christ the Redeemer
*31 metres – wavelength of the broadcast radio shortwave band at 9.7 MHz
*32 metres – length of one Minute and second of arc, arcsecond of latitude on the surface of the Earth
*33.3 metres – height of the De Noord, the tallest windmill in the world
*34 metres – height of the Split Point Lighthouse in Aireys Inlet, Victoria, Australia
*40 metres – wingspan of the Mil Mi-26, the largest helicopter
*40 metres – average depth beneath the seabed of the Channel tunnel
*49 metres – wavelength of the broadcast radio shortwave band at 6.1 MHz
*50 metres – length of a road train
*50 metres – height of the Arc de Triomphe
*55 metres – height of the Leaning Tower of Pisa
*62 metres – wingspan of Concorde
*62.5 metres – height of Pyramid of Djoser
*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
*73 metres – wingspan of a Airbus A380
*73 metres – height of the Taj Mahal
*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 (''Liberty Enlightening the World'')
*96 metres – height of Big Ben
*100 metres – wavelength of the lowest shortwave radio frequency, 1 E6 Hz, 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 an association football 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 – height of a saguaro cactus
*12 metres – length of a whale shark, largest living fish
*12 metres – wingspan of a ''Quetzalcoatlus'', a pterosaur
*12.8 metres – length of a ''Titanoboa'', the largest snake to have ever lived
*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
*16 metres – length of a sperm whale, the largest toothed whale
*18 metres – height of a ''Sauroposeidon'', the tallest-known dinosaur
*20 metres – length of a ''Leedsichthys'', the largest-known fish to have lived
*21 metres – height of High Force waterfall in England
*30.5 metres – length of the lion's mane jellyfish, the largest jellyfish in the world
*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'', the longest-known dinosaur and longest vertebrate
*52 metres – height of Niagara Falls
*55 metres – length of a bootlace worm, the longest-known animal
*66 metres – highest possible sea level rise due to a complete melting of all ice on Earth
*83 metres – height of a western hemlock
*84 metres – height of General Sherman Tree, General Sherman, the largest tree in the world

Astronomical

*30 metres – diametre of , a rapidly spinning meteoroid
*30.8568 metres – 1 femtoparsec
*32 metres – approximate diametre of 2008 HJ, a small meteoroid

1 hectometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to 100 metre, metres (10² m).
To compare different orders of magnitude this section lists lengths between 100 metres and 1,000 metres (1 kilometre, kilometre).

Conversions

100 metres (sometimes termed a hectometre) is equal to:

*328 foot (length), feet
*one side of a 1 E+4 m², 1 hectare square
*a fifth of a modern li (Chinese unit), li, a Chinese unit of measurement
*the approximate distance travelled by light in 300 nanoseconds

Human-defined scales and structures

*100 metres – wavelength of the highest medium wave radio frequency, 1 E6 Hz, 3 MHz
*100 metres – spacing of location marker posts on British motorways
*110 metres – height of the Saturn V
*122 metres – height of the SpaceX Starship, Starship, the tallest rocket currently under development by SpaceX
*138.8 metres – height of the Great Pyramid of Giza (Pyramid of Cheops)
*139 metres – height of the world's tallest roller coaster, Kingda Ka
*157 metres – height of the Cologne Cathedral
*162 metres – height of the Ulm Minster, the tallest church building in the world
*165 metres – height of the Dushanbe Flagpole, the tallest flagpole from May 2011 to September 2014
*169 metres – height of the Washington Monument
*171 metres – height of the Jeddah Flagpole, the tallest flagpole from September 2014 to December 2021
*182 metres – height of the ''Statue of Unity'', the world's tallest statue
*187 metres – shortest wavelength of the broadcast radio AM band, 1 E6 Hz, 1600 kHz
*192 metres – height of the Gateway Arch
*202 metres – height of the Cairo Flagpole, the tallest flagpole as of December 2021
*202 metres – length of the Széchenyi Chain Bridge connecting Buda and Pest
*220 metres – height of the Hoover Dam
*245 metres – length of the LZ 129 Hindenburg
*270 metres – length of the ''Titanic''
*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 (Auckland), Sky Tower, the tallest free-standing structure in the Southern Hemisphere (1996–2022)
*330 metres – height of the Eiffel Tower (including antenna)
*336 metres – height of the world's tallest bridge as of October 2023, the Millau Viaduct
*364.75 metres – length of the Icon of the Seas
*390 metres – height of the Empire State Building
*400–800 metres – approximate heights of the world's tallest skyscrapers from 1931 to 2010
*458 metres – length of the Knock Nevis, the world's largest supertanker
*553.33 metres – height of the CN Tower, the tallest structure in North America
*555 metres – longest wavelength of the broadcast radio AM band, 1 E5 Hz, 540 kHz
*630 metres – height of the KVLY-TV mast, one of the tallest structures in the world
*646 metres – height of the Warsaw radio mast, the world's tallest structure until its collapse in 1991
*679 metres – height of Merdeka 118, the second tallest structure in Kuala Lumpur, Malaysia
*828 metres – height of Burj Khalifa, world's tallest structure since 17 January 2009
*1,000 metres – wavelength of the lowest mediumwave radio frequency, 1 E5 Hz, 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 (tree), 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
*947 metres – height of the Tugela Falls, the highest waterfall in Africa
*979 metres – height of the Angel Falls, the world's highest free-falling waterfall (Venezuela)

Astronomical

*270 metres – length of 99942 Apophis
*535 metres – length of 25143 Itokawa, a small asteroid visited by a spacecraft

1 kilometre

The ' ( SI symbol: ') is a unit of length in the metric system equal to  metre, metres (10³ m).
To help compare different orders of magnitude, this section lists lengths between 1 kilometre and 10 kilometre, kilometres (10³ and 10⁴ metre, metres).

Conversions

1 kilometre, kilometre (unit symbol km) is equal to:

*1,000 metre, metres
*0.621371 miles
*1,093.61 yards
*3,280.84 foot (length), feet
*39,370.1 inches
*100,000 centimetre, centimetres
*1,000,000 millimetre, millimetres
*Side of a square (geometry), square of area 1 E+6 m², 1 Km², km²
*Radius of a circle of area Pi, π km²

Human-defined scales and structures

*1 km – wavelength of the highest long wave radio frequency, 1 E5 Hz, 300 kHz
*1.008 km – proposed height of the Jeddah Tower, a megatall skyscraper under construction in Saudi Arabia
*1.280 km – span of the Golden Gate Bridge (distance between towers)
*1.609 km – 1 statute mile
*1.852 km – 1 nautical mile, equal to 1 arcminute of latitude at the surface of the Earth
*1.991 km – span of the Akashi Kaikyō Bridge
*2.309 km – axial length of the Three Gorges Dam, the largest dam in the world located in China
*3.991 km – length of the Akashi Kaikyō Bridge, longest suspension bridge in the world
*4 km – width of Central Park
*5.072 km – elevation of Tanggula Mountain Pass, below highest peak in the Tanggula Mountains, highest railway pass in the world
*5.8 km – elevation of Cerro Aucanquilcha, highest road in the world, located in Chile
*List of longest runways, 98 airports have paved runways from 4 km to 5.5 km in length.
*8 km – length of Palm Jebel Ali, an artificial island built off the coast of Dubai
*9.8 km – length of The World (archipelago), The World, an artificial archipelago that is also built off the coast of Dubai, whose islands resemble a world map

Nature

*1.5 km – distance sound travels in water in one second

Geographical

*1.637 km – deepest dive of Lake Baikal in Russia, the world's largest freshwater lake
*2.228 km – height of Mount Kosciuszko, highest point on mainland Geography of Australia, Australia
*Most of Manhattan is from 3 to 4 km wide.
*3.776 km – height of Mount Fuji, highest peak in Japan
*4.478 km – height of Matterhorn
*4.509 km – height of Mount Wilhelm, highest peak in Papua New Guinea
*4.810 km – height of Mont Blanc, highest peak in the Alps
*4.884 km – height of Carstensz Pyramid, highest peak in Oceania
*4.892 km – height of Mount Vinson, highest peak in Antarctica
*5.610 km – height of Mount Damavand, highest peak in Iran
*5.642 km – height of Mount Elbrus, highest peak in Europe
*5.895 km – height of Mount Kilimanjaro, highest peak in Africa
*6.081 km – height of Mount Logan, highest peak in Canada
*6.190 km – height of Denali, highest peak in North America
*6.959 km – height of Aconcagua, highest peak in South America
*7.5 km – depth of Cayman Trench, deepest point in the Caribbean Sea
*8.611 km – height of K2, second highest peak on Earth
*8.848 km – height of Mount Everest, highest peak on Earth, on the border between Nepal and China

Astronomical

*1 km – diametre of 1620 Geographos
*1 km – very approximate size of the smallest-known moons of Jupiter
*1.4 km – diametre of Dactyl (asteroid), Dactyl, the first confirmed asteroid moon
*4.8 km – diametre of 5535 Annefrank, an inner belt asteroid
*5 km – diametre of 3753 Cruithne
*5 km – length of PSR B1257+12
*8 km – diametre of Themisto (moon), Themisto, one of Jupiter's moons
*8 km – diametre of the Vela Pulsar
*8.6 km – diametre of Callirrhoe (moon), Callirrhoe, also known as Jupiter XVII
*9.737 km – length of PSR B1919+21

10 kilometres (1 myriametre)

To help compare different orders of magnitude, this section lists lengths between 10 and 100 kilometre, kilometres (10⁴ to 10⁵ metre, metres). 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- (sometimes also written as myrio-) is obsolete and was not included among the SI prefixes, prefixes when the International System of Units was introduced in 1960.

Conversions

10 kilometres is equal to:

*10,000 metre, metres
*About 6.2 miles
*1 ''mil (the Scandinavian mile)'', now standardized as 10 km:
**1 mil, the unit of measure commonly used in Norway and SwedenHaugen, Einar, ''Norwegian English Dictionary,'' 1965, Oslo: Universitetsforlaget and Madison: University of Wisconsin Press, s.v. mil used to be 11,295 m in Norway and 10,688 m in Sweden.
*''Parasang, farsang'', unit of measure commonly used in Iran and Turkey

Sports

*42.195 km – length of the marathon

Human-defined scales and structures

*18 km – cruising altitude of Concorde
*27 km – circumference of the Large Hadron Collider, the largest and highest energy particle accelerator
*34.668 km – highest manned balloon flight (Malcolm D. Ross and Victor E. Prather on 4 May 1961)
*38.422 km – length of the Second Lake Pontchartrain Causeway in Louisiana, U.S.
*39 km – undersea portion of the Channel tunnel
*53.9 km – length of the Seikan Tunnel, , the longest rail tunnel in the world
*77 km – rough total length of the Panama Canal

Geographical

*10 km – height of Mauna Kea in Hawaii, measured from its base on the ocean floor
*11 km – deepest-known point of the ocean, Challenger Deep in the Mariana Trench
*11 km – average height of the troposphere
*14 km – width of the Strait of Gibraltar
*21 km – length of Manhattan
*22 km – narrowest width of the Cook Strait between New Zealand's main islands
*23 km – depth of the 1931 Dogger Bank earthquake, largest earthquake ever recorded in the United Kingdom, in 1931 at the Dogger Bank of the North Sea
*34 km – narrowest width of the English Channel at the Strait of Dover
*50 km – approximate height of the stratosphere
*90 km – width of the Bering Strait

Astronomical

*10 km – diametre of the most massive neutron stars (3–5 solar masses)
*13 km – mean diametre of Deimos (moon), Deimos, the smaller moon of Mars
*20 km – diametre of the least massive neutron stars (1.44 solar masses)
*20 km – diametre of Leda (moon), Leda, one of Jupiter's moons
*20 km – diametre of Pan (moon), Pan, one of Saturn's moons
*22 km – diametre of Phobos (moon), Phobos, the larger moon of Mars
*27 km – height of Olympus Mons above the Mars reference level, the highest-known mountain of the Solar System
*30.8568 km – 1 picoparsec
*43 km – diametre difference of Earth's equatorial bulge
*66 km – diametre of Naiad (moon), Naiad, the innermost of Neptune'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 Fédération Aéronautique Internationale, FAI defines spaceflight to begin.

To help compare orders of magnitude, this section lists lengths between 100 and 1,000 kilometre, kilometres (10⁵ and 10⁶ metre, metres).

Conversions

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

Human-defined scales and structures

*100 km – the Karman line: the internationally recognized boundary of outer space
*105 km – distance from Giridih to Bokaro Steel City, Bokaro
*109 km – length of High Speed 1 between London and the Channel Tunnel
*130 km – range of a Scud-A missile
*163 km – length of the Suez Canal
*164 km – length of the Danyang–Kunshan Grand Bridge
*213 km – length of Paris Métro
*217 km – length of the Grand Union Canal
*223 km – length of the Madrid Metro
*300 km – range of a Scud-B missile
*386 km – altitude of the International Space Station
*408 km – length of the London Underground (active track)
*460 km – distance from London to Paris
*470 km – distance from Dublin to London 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

*42 km – width of Singapore
*75 km – width of Rhode Island
*111 km – distance covered by one degree of latitude on Earth's surface
*120 km – width of Brunei
*180 km – distance between Mumbai and Nashik
*200 km – width of Qatar
*203 km – length of Sognefjorden, the third-largest fjord in the world
*220 km – distance between Pune and Nashik
*240 km – width of Rwanda
*240 km – widest width of the English Channel
*400 km – width of West Virginia
*430 km – length of the Pyrenees
*450 km – length of the Grand Canyon
*500 km – widest width of Geography of Sweden, Sweden from east to west
*501 km – width of Uganda
*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
*800 km – width of Germany
*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
*970 km – distance from Land's End to John o' Groats as the crow flies

Astronomical

*100 km – the altitude at which the Fédération Aéronautique Internationale, FAI defines spaceflight to begin
*167 km – diametre of Amalthea (moon), Amalthea, one of Jupiter's inner moons
*200 km – width of Valles Marineris
*220 km – diametre of Phoebe (moon), Phoebe, the largest of Saturn's outer moons
*300 km – the approximate distance travelled by light in one millisecond
*340 km – diametre of Nereid (moon), Nereid, the third-largest moon of Neptune which has a highly Elliptic orbit, elliptical orbit
*350 km – lower bound of Low Earth orbit
*420 km – diametre of Proteus (moon), Proteus, the second-largest moon of Neptune
*468 km – diametre of the asteroid 4 Vesta
*472 km – diametre of Miranda (moon), Miranda, one of Uranus's major moons
*974.6 km – greatest diametre of Ceres (dwarf planet), 1 Ceres, the largest Solar System asteroid

1 megametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to  metre, metres (10⁶ m).
To help compare different orders of magnitude, this section lists lengths starting at 10⁶ m (#1 megametre, 1 Mm or 1,000 kilometre, km).

Conversions

1 megametre is equal to:
* 1000 km
* (one million metres)
* approximately 621.37 miles

Human-defined scales and structures

*2.100 Mm – length of proposed Iran-Pakistan-India gas pipe
*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, 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
*1.100 Mm – length of Italy
*1.200 Mm – length of California
*1.200 Mm – width of Texas
*1.500 Mm – length of the Gobi Desert
*1.600 Mm – length of the Namib, the oldest desert on Earth
*2.000 Mm – distance from Beijing to Hong Kong as the crow flies
*2.300 Mm – length of the Great Barrier Reef
*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
*4.000 Mm – length of the Kalahari Desert
*4.350 Mm – length of the Yellow River
*4.600 Mm – width of the Mediterranean Sea
*4.800 Mm – length of the Sahara
*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
*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 – diametre of Charon (moon), Charon, the largest moon of Pluto
*1.280 Mm – diametre of the trans-Neptunian object 50000 Quaoar
*1.436 Mm – diametre of Iapetus (moon), Iapetus, one of Saturn's major moons
*1.578 Mm – diametre of Titania (moon), Titania, the largest of Uranus's moons
*1.960 Mm – estimated longest axis of Haumea (dwarf planet), Haumea
*2.326 Mm – diametre of the dwarf planet Eris (dwarf planet), Eris, the largest trans-Neptunian object found to date
*2.376 Mm – diametre of Pluto
*2.707 Mm – diametre of Triton (moon), Triton, largest moon of Neptune
*3.122 Mm – diametre of Europa (moon), Europa, the smallest Galilean satellite of Jupiter
*3.476 Mm – diametre of Earth's Moon
*3.643 Mm – diametre of Io (moon), Io, a moon of Jupiter
*4.821 Mm – diametre of Callisto (moon), Callisto, a moon of Jupiter
*4.879 Mm – diametre of Mercury (planet), Mercury
*5.150 Mm – diametre of Titan (moon), Titan, the largest moon of Saturn
*5.262 Mm – diametre of Jupiter's moon Ganymede (moon), Ganymede, the largest moon in the Solar System
*6.371 Mm – Earth radius, radius of Earth
*6.792 Mm – diametre of Mars

10 megametres

To help compare different orders of magnitude, this section lists lengths starting at 10⁷ metre, metres (#10 megametre, 10 megametres or 10,000 kilometre, kilometres).

Conversions

10 megametres (10 Mm) is
*6,215 miles
*side of a square (geometry), square of area 100,000,000 square kilometre, square kilometres (km²)
*radius of a circle 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 Prefecture, 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 Seas'')

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, metre was based on this length)
*40.000 Mm – length of the Ring of Fire
*60.000 Mm – total length of the mid-ocean ridges

Astronomical

*12.000 Mm – diametre of Sirius, Sirius B, a white dwarf
*12.104 Mm – diametre of Venus
*12.742 Mm – diametre of Earth
*12.900 Mm – minimum distance of the meteoroid from the centre of Earth on 31 March 2004, closest on record
*14.000 Mm – smallest diametre 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 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 – diametre of Neptune
*51.118 Mm – diametre of Uranus

100 megametres

To help compare different orders of magnitude, this section lists lengths starting at 10⁸ metre, metres (#100 megametre, 100 megametres or 100,000 kilometre, kilometres or 62,150 miles).

*102 Mm – diametre of HD 149026 b, an unusually dense gas giant, Jovian planet
*115 Mm – width of Saturn's Rings
*120 Mm – diametre of EBLM J0555-57Ab, the smallest-known star
*120 Mm – diametre of Saturn
*142 Mm – diametre of Jupiter, the largest planet in the Solar System
*170 Mm – diametre of TRAPPIST-1, a star discovered to have seven planets around it
*174 Mm – diametre of OGLE-TR-122b, one of the smallest known stars
*180 Mm – average distance covered during life
*215 Mm – diametre of Proxima Centauri, the nearest star to the Solar System
*257 Mm – diametre of TrES-4b, TrES-4, one of the largest exoplanets
*260 Mm – diametre of the Barnard's Star
*272 Mm – diametre of WASP-12b
*299.792 Mm – one light-second; the distance light travels in vacuum in one second (see speed of light)
*314 Mm – diametre of CT Cha b
*384.4 Mm (238,855 mi) – average Lunar distance (astronomy), Earth–Moon distance
*671 Mm – separation between Jupiter and Europa (moon), Europa
*696 Mm – Solar radius, radius of Sun
*989 Mm – diametre of Epsilon Indi, one of the nearest stars to Earth

1 gigametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to  metre, metres (10⁹ m).
To help compare different distances this section lists lengths starting at 10⁹ metre, metres (1 gigametre (Gm) or 1 billion metre, metres).

*1.2 Gm – separation between Saturn and Titan (moon), Titan
*1.39 Gm – diametre of Sun
*1.5 Gm – orbit from Earth of the James Webb Space Telescope
*1.71 Gm – diametre of Alpha Centauri A, one of the closest stars.
*2.19 Gm – closest approach of Comet Lexell to Earth, happened on 1 July 1770; closest comet approach on record
*2.38 Gm – diametre of Sirius A, brightest naked eye star.
*3 Gm – total length of "wiring" in the human brain
*3.5 Gm – diametre of Vega
*4.2 Gm – diametre of Algol B
*4.3 Gm – circumference of Sun
*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 interferometre of the Laser Interferometre Space Antenna (LISA) planned to start observations sometime in the 2030s.''
*7.9 Gm – diametre of Bellatrix, Gamma Orionis, a blue dwarf or blue giant
*9.0 Gm – estimated diametre 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, metres (10 1 gigametre, gigametres (Gm) or 10 million kilometre, kilometres, or 0.07 astronomical units).

*10.4 Gm – diametre of Spica, an oval-shaped blue giant star and a List of supernova candidates, nearby supernova candidate.
*12.6 Gm – diametre of Pollux (star), Pollux, the closest red giant star to the Sun. It is a red clump star fusing helium into carbon at its core.
*15 Gm – closest distance of Comet Hyakutake from Earth
*18 Gm – one light-minute (see yellow sphere in right-hand diagram)
*24 Gm – radius of a heliostationary orbit
*30.8568 Gm – 1 microparsec
*35 Gm – approximate diametre of Arcturus, a close red giant star. It is on the red giant branch, fusing hydrogen into helium in a shell surrounding an inert helium core.
*46 Gm – Apsis, perihelion distance of Mercury (planet), Mercury (yellow ellipse on the right)
*55 Gm – 60,000-year perigee of Mars (last achieved on 27 August 2003)
*58 Gm – average passing distance between Earth and Mars at the moment they overtake each other in their orbits
*61 Gm – diametre of Aldebaran, a red giant branch star (large star on right) They derived an angular diametre of 20.58±0.03 milliarcsec, which given a distance of 65 light-years yields a diametre of 61 million km.
*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)

100 gigametres

To help compare distances at different orders of magnitude this section lists lengths starting at 10¹¹ metre, metres (100 #1 gigametre, gigametre or 100 million kilometre, kilometres or 0.7 astronomical units).

*103 Gm (0.69 au) – diametre of Rigel
*109 Gm (0.7 au) – distance between Venus and the Sun
*149.6 Gm (93.0 million mi; 1.0 au) – average distance between the Earth and the Sun – the original definition of the astronomical unit
*163 Gm (1.09 au) – diametre of Deneb, a blue supergiant
*228 Gm (1.5 au) – distance between Mars and the Sun
*255 Gm (1.7 au) – diametre of Enif, a small red supergiant star in the constellation Pegasus (constellation), Pegasus
*511 Gm (3.4 au) – average diametre of Mira, a pulsating red giant and the progenitor of the Mira variables. It is an asymptotic giant branch star.
*570 Gm (3.8 au) – length of the tail of Comet Hyakutake measured by ''Ulysses (spacecraft), Ulysses''; the actual value could be much higher
*590 Gm (3.9 au) – diametre of the Pistol Star, a blue hypergiant star
*591 Gm (4.0 au) – minimum distance between the Earth and Jupiter
*780 Gm (5.2 au) – average distance between Jupiter and the Sun
*785 Gm (5.25 au) – diametre of Rho Cassiopeiae, a rare yellow hypergiant star
*947 Gm (6.4 au) – diametre of Antares, Antares A
*965 Gm (6.4 au) – maximum distance between the Earth and Jupiter

1 terametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to  metre, metres (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 Tm – 6.7 au – diametre of the red supergiant Betelgeuse based on multiple angular diametre estimates
*1.032 Tm – 6.9 au – diametre of the blue hypergiant Eta Carinae (at optical depth 2/3)
*1.079 Tm – 7.2 au – one light-hour
*1.114 Tm – 7.5 au – diametre of WOH G64, a star in the Large Magellanic Cloud, which recently transformed from a red hypergiant to a yellow hypergiant
*1.4 Tm – 9.5 au – average distance between Saturn and the Sun
*1.47 Tm – 9.9 au – diametre of HR 5171 A, a yellow hypergiant star.
*1.5 Tm – 10 au – estimated diametre of VV Cephei A, a red hypergiant with a blue dwarf companion.
*1.75 Tm – 11.7 au – estimated diametre of Mu Cephei, a red supergiant (possibly hypergiant) among the List of largest stars, largest-known stars.Table 4 in
*2 Tm – 13.2 au – estimated diametre of VY Canis Majoris, a red hypergiant that is among the list of largest stars, largest-known stars
*2.142 Tm – 14.3 au – estimated diametre of WOH G64, prior to its transformation into a yellow hypergiant.
*2.9 Tm – 19.4 au – average distance between Uranus and the Sun
*4.4 Tm – 29.4 au – Apsis, perihelion distance of Pluto
*4.5 Tm – 30.1 au – average distance between Neptune 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
*6.0 Tm – 40.5 au – distance from Earth at which the Pale Blue Dot photograph was taken.
*7.3 Tm – 48.8 au – Apsis, aphelion distance of Pluto
*7.5 Tm – 50.1 au – outer boundary 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 – diametre 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
*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
*18 Tm – 123.5 AU – distance between the Sun to the farthest dwarf planet in the Solar System, the Farout 2018 VG18
*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
*24.8 Tm – 166 AU – distance to ''Voyager 1'' as of November 2024
*25.9 Tm – 173 AU – one light-day
*30.8568 Tm – 206.3 AU – 1 milliparsec
*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 diametre of H1821+643, one of the most massive black holes known
*181 Tm – 1210 AU – one light-week
*308.568 Tm – 2063 AU – 1 centiparsec
*757 Tm – 5059 AU – radius of the Stingray Nebula
*777 Tm – 5180 AU – one light-month

1 petametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to 10¹⁵ metre, metres.
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 diametre/2) = 0.2 light-year. Distance = 3.3 ± 0.9 light-year, kly; angular diametre = 20 arcseconds
*3.08568 Pm = 20,626 AU = 1 deciparsec
*4.7 Pm = 30,000 AU = half-light-year diametre 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 light travels 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
*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
*94.6 Pm – 1 light-decade

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 – Diametre 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 the Sun. Its faintness gives an idea how the Sun would appear when viewed from this distance.
*308.568 Tm – 32.6 light-years – 1 dekaparsec
*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
*946 Pm – 1 light-century

1 exametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to 10¹⁸ metre, metres. 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 – diametre of Messier 13 (a typical globular cluster)
*1.6 Em – 172 ± 12.5 light-years – diametre of Omega Centauri (one of the largest-known globular clusters, perhaps containing over a million stars)
*3.08568 Em – 326.1 light-years – 1 hectoparsec
*3.1 Em – 310 light-years – distance to Canopus (star), Canopus according to ''Hipparcos''Vizier catalog entry
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*3.9 Em – 410 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
*8.2 Em – 860 light-years – distance to Rigel according to ''Hipparcos''
*9.4 Em — 1 light-millennium – 1000 light-years

10 exametres

To help compare different orders of magnitude, 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 – diametre 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
*94.6073 Em – 1 light-decamillennium = 10,000 light-years

100 exametres

To help compare different orders of magnitude, this section lists distances starting at 100 exametre, Em (10²⁰ m or 11,000 light-years).

*150 Em – 16,000 light-years – diametre of the Small Magellanic Cloud, a dwarf galaxy orbiting the Milky Way
*200 Em – 21,500 light-years – distance to OGLE-2005-BLG-390Lb
*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
*400 Em – 48,000 light years – diametre of the Fireworks Galaxy
*830 Em – 88,000 light-years – distance to the Sagittarius Dwarf Elliptical Galaxy
*946 Em – 1 light-centum-millennium = 100,000 light-years

1 zettametre

The ' ( SI symbol: ') is a unit of length in the metric system equal to 10²¹ metre, metres.
To help compare different orders of magnitude, 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 diametre 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
*9.5 Zm – 1 light-megaannum = 1,000,000 light-years

10 zettametres

To help compare different orders of magnitude, 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, the nearest major 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, 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 of length in the metric system equal to 10²⁴ metre, metres.

To help compare different orders of magnitude, 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 – diametre of the Local Supercluster
*2.17 Ym – 1 light-galactic-years – 230 million light-years
*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
*3.15 Ym – 330 million light years – diametre of the Boötes Void
*3.2 Ym – 338 million light-years – distance to 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 – diametre of the Eridanus Supervoid

10 yottametres

To help compare different orders of magnitude, 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, 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 – diametre 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 diametre 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 of length in the metric system equal to 10²⁷ metre, metres.

To help compare different orders of magnitude, this section lists distances starting at 1 Rm (10²⁷ m or 105.7 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#Cosmology, infinite (see Shape of the universe) as previously mentioned.
*2.764 Rm - 292.2 billion light-years – circumference of the observable universe, as it is in the shape of a sphere.
*≈10^1010122light-years – the possible size of the universe after cosmological inflation.
*≈∞ light-years – theoretical size of the multiverse if it exists.

See also

*Fermi problem
*Scale (analytical tool)
*Spatial scale
*The Scale of the Universe

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).

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