This is a glossary of terms used in meteoritics, the science of
meteorites.
#
*
2 Pallas
Pallas (minor-planet designation: 2 Pallas) is the second asteroid to have been discovered, after Ceres. It is believed to have a mineral composition similar to carbonaceous chondrite meteorites, like Ceres, though significantly less hydr ...
– an asteroid from the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and one of the likely parent bodies of the
CR meteorites.
*
4 Vesta
Vesta (minor-planet designation: 4 Vesta) is one of the largest objects in the asteroid belt, with a mean diameter of . It was discovered by the German astronomer Heinrich Wilhelm Matthias Olbers on 29 March 1807 and is named after Vesta, the ...
– second-largest asteroid in the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and likely source of the
HED meteorite
HED meteorites are a clan (subgroup) of achondrite meteorites. HED stands for "howardite– eucrite– diogenite".
These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the ma ...
s.
*
221 Eos
Eos (minor planet designation: 221 Eos) is a large main-belt asteroid that was discovered by Austrian astronomer Johann Palisa on January 18, 1882, in Vienna. In 1884, it was named after Eos, the Greek goddess of the dawn, to honour the opening ...
– an asteroid from the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and one of the likely parent bodies of the
CO meteorites.
*
289 Nenetta – an asteroid from the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and one of the likely parent bodies of the
angrite
Angrites are a rare group of achondrites consisting mostly of Al-Ti bearing diopside, hedenbergite, olivine, anorthite and troilite with minor traces of phosphate and metals. The group is named for the Angra dos Reis meteorite. They are the oldes ...
s.
*
3103 Eger – an asteroid from the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and one of the likely parent bodies of the
aubrites.
*
3819 Robinson – an asteroid from the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and one of the likely parent bodies of the
angrite
Angrites are a rare group of achondrites consisting mostly of Al-Ti bearing diopside, hedenbergite, olivine, anorthite and troilite with minor traces of phosphate and metals. The group is named for the Angra dos Reis meteorite. They are the oldes ...
s.
*
IA meteorite – an
iron meteorite group now part of the IAB group/complex.
*
IAB meteorite
IAB meteorites are a group of iron meteorites according to their overall composition and a group of primitive achondrites because of silicate inclusions that show a strong affinity to winonaites and chondrites.
Description
The IAB meteorites are c ...
– an
iron meteorite and
primitive achondrite of the IAB group/complex.
*
IB meteorite – an
iron meteorite group now part of the IAB group/complex.
*
IC meteorite – an
iron meteorite that is part of the IC group.
A
*
Ablation
Ablation ( la, ablatio – removal) is removal or destruction of something from an object by vaporization, chipping, erosive processes or by other means. Examples of ablative materials are described below, and include spacecraft material for a ...
– the process of a meteorite losing mass during the passage through the atmosphere.
*
Acapulcoite – a group of
primitive achondrites.
*
Accretion
Accretion may refer to:
Science
* Accretion (astrophysics), the formation of planets and other bodies by collection of material through gravity
* Accretion (meteorology), the process by which water vapor in clouds forms water droplets around nucl ...
– the process in which matter of the
protoplanetary disk coalesces to form planetesimals.
*
Achondrite
An achondrite is a stony meteorite that does not contain chondrules. It consists of material similar to terrestrial basalts or plutonic rocks and has been differentiated and reprocessed to a lesser or greater degree due to melting and recrystalliz ...
– a differentiated
meteorite (meaning without
chondrules
A chondrule (from Ancient Greek χόνδρος ''chondros'', grain) is a round grain found in a chondrite. Chondrules form as molten or partially molten droplets in space before being accreted to their parent asteroids. Because chondrites repres ...
).
*
Aerolite – an old term for
stony meteorites.
*
ALH – an abbreviation used for meteorites from
Allan Hills
The Allan Hills are a group of hills at the end of the Transantarctic Mountains System, located in Oates Land and Victoria Land regions of Antarctica.
They are mainly ice free and about long, lying just north-west of the Coombs Hills near the ...
.
*
Allan Hills 84001
Allan Hills 84001 (ALH84001) is a fragment of a Martian meteorite that was found in the Allan Hills in Antarctica on December 27, 1984, by a team of American meteorite hunters from the ANSMET project. Like other members of the shergottite–nakh ...
– is an exotic meteorite from
Mars that does not fit into any of the SNC groups and was thought to contain evidence for life on Mars.
*
Allende meteorite
The Allende meteorite is the largest carbonaceous chondrite ever found on Earth. The fireball was witnessed at 01:05 on February 8, 1969, falling over the Mexican state of Chihuahua. After it broke up in the atmosphere, an extensive search for p ...
– is the largest carbonaceous chondrite ever found on Earth.
*
Amphoterite
''Amphoterite'' is an obsolete classification of chondritic meteorites that are now classified as LL (Low Iron and Low total metal content) types.
Most of the iron in these types of meteorites is present as ironoxide in the minerals (e.g. olivin ...
– an obsolete classification of chondritic meteorites that are now classified as LL.
*
Angrite
Angrites are a rare group of achondrites consisting mostly of Al-Ti bearing diopside, hedenbergite, olivine, anorthite and troilite with minor traces of phosphate and metals. The group is named for the Angra dos Reis meteorite. They are the oldes ...
– a
basalt
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...
ic meteorite.
*
ANSMET
ANSMET (Antarctic Search for Meteorites) is a program funded by the Office of Polar Programs of the National Science Foundation that looks for meteorites in the Transantarctic Mountains. This geographical area serves as a collection point for mete ...
– the ''An''tarctic ''S''earch for ''Met''eorites is a scientific program that looks for meteorites in the
Transantarctic Mountains.
*
Asteroidal achondrite – an achondrite that differentiated on an asteroid or planetesimal (see
planetary achondrite)
*
Asteroid spectral types
An asteroid spectral type is assigned to asteroids based on their emission spectrum, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies that are not internally differentiated ...
– classification of asteroids according to their spectra.
*
Ataxite
Ataxites (from Greek meaning "without structure") are a structural class of iron meteorites with a high nickel content and show no Widmanstätten patterns upon etching.
Characteristics
Ataxites are composed mainly of meteoric iron, a native metal ...
– an
iron meteorite that has no visible structures when etched.
B
*
Basaltic achondrite – a grouping of
basalt
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...
meteorites (
HED meteorite
HED meteorites are a clan (subgroup) of achondrite meteorites. HED stands for "howardite– eucrite– diogenite".
These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the ma ...
s +
Angrite
Angrites are a rare group of achondrites consisting mostly of Al-Ti bearing diopside, hedenbergite, olivine, anorthite and troilite with minor traces of phosphate and metals. The group is named for the Angra dos Reis meteorite. They are the oldes ...
)
*
Brachinite – either a primitive achondrite or an asteroidal achondrite
*
Bolide
A bolide is normally taken to mean an exceptionally bright meteor, but the term is subject to more than one definition, according to context. It may refer to any large crater-forming body, or to one that explodes in the atmosphere. It can be a s ...
– is an extremely bright meteor, especially one that explodes in the atmosphere
C
* C – can refer to
carbonaceous chondrite
Carbonaceous chondrites or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites. The C chondrites represent only a small prop ...
or to an
iron meteorite designation (Roman numeral and letter).
*
Carbonaceous chondrite
Carbonaceous chondrites or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites. The C chondrites represent only a small prop ...
*
CAI
Cai or CAI may refer to:
Places
* Cai (state), a state in ancient China
* Caí River, Rio Grande do Sul, Brazil
* Cái River, Vietnam
* Cairo International Airport (IATA airport code)
* Caithness, a historic county in Scotland (Chapman code)
...
– an abbreviation of
Calcium-aluminium-rich inclusion
*
Calcium-aluminium-rich inclusion
*
Chassignite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percen ...
*
Chondrite – stony meteorites unmodified by melting or differentiation of the parent body
*
Chondrule – millimetre-scale round grains found in chondrites
*
Clan
A clan is a group of people united by actual or perceived kinship
and descent. Even if lineage details are unknown, clans may claim descent from founding member or apical ancestor. Clans, in indigenous societies, tend to be endogamous, meanin ...
– meteorites that are not similar enough to form a group, but are also not too different from each other to be put in separate classes.
*
Class
Class or The Class may refer to:
Common uses not otherwise categorized
* Class (biology), a taxonomic rank
* Class (knowledge representation), a collection of individuals or objects
* Class (philosophy), an analytical concept used differently ...
– two or more groups that have a similar chemistry and oxygen isotope ratios.
* Compositional type – a classification based on overall composition, for example stony, iron, stony-iron (as introduced by Maskelyne). Can also refer to the composition deduced from spectroscopy of asteroids.
*
Condensation
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to ...
– the process of chemicals changing from the gaseous to the solid phase during the cooling of the
protoplanetary disk.
*
Condensation sequence – the sequence of minerals that changes from the gaseous to the solid state while the
protoplanetary disk cools.
*
Cosmic dust – small interplanetary and interstellar particles that are similar to meteorites (See
Micrometeorite).
*
Cosmochemistry
Cosmochemistry (from Greek κόσμος ''kósmos'', "universe" and χημεία ''khemeía'') or chemical cosmology is the study of the chemical composition of matter in the universe and the processes that led to those compositions. This is done ...
– the study of the chemical composition of the universe and its constituents, and the processes that produced those compositions.
D
*
Dar al Gani – a meteorite field in the Libyan Sahara.
*
Desert glass – natural glass found in deserts formed from the silica in sand as a result of lightning strikes or meteor impacts.
* Differentiated – a meteorite that has undergone
igneous differentiation
In geology, igneous differentiation, or magmatic differentiation, is an umbrella term for the various processes by which magmas undergo bulk chemical change during the partial melting process, cooling, emplacement, or eruption. The sequence of ( ...
. (See:
achondrite
An achondrite is a stony meteorite that does not contain chondrules. It consists of material similar to terrestrial basalts or plutonic rocks and has been differentiated and reprocessed to a lesser or greater degree due to melting and recrystalliz ...
)
*
Differentiation – usually the process of a planetesimal forming an iron core and silicate mantle.
*
Duo
Duo may refer to:
Places
* Duo, West Virginia, an unincorporated community and coal town in Greenbrier County, West Virginia
* Duo, Tampere, a shopping centre in Hervanta, Tampere, Finland
* DUO, a twin-tower development in Singapore
Arts, enter ...
– a grouping of two meteorites that share similar characteristics (see Grouplet).
E
* E – can refer to
enstatite chondrite
Enstatite chondrites (E-type chondrites) are a rare form of meteorite, rich in the mineral enstatite. Only about 200 E-Type chondrites are currently known, comprising about 2% of the chondrites that fall on Earth.Norton, O.R. and Chitwood, L.A. ...
or to an
iron meteorite designation (Roman numeral and letter).
*
Eagle Station grouplet – a set of pallasite meteorite specimen that do not fit into any of the defined pallasite groups.
* Electrophonic bolide – a meteoroid which produces a measurable discharge of electromagnetic energy (
EMP) during its passage through the atmosphere.
*
Enstatite achondrite – a meteorite that is mostly composed of
enstatite
Enstatite is a mineral; the magnesium endmember of the pyroxene silicate mineral series enstatite (MgSiO3) – ferrosilite (FeSiO3). The magnesium rich members of the solid solution series are common rock-forming minerals found in igneous and m ...
. Usually part of the
aubrite group.
*
Enstatite chondrite
Enstatite chondrites (E-type chondrites) are a rare form of meteorite, rich in the mineral enstatite. Only about 200 E-Type chondrites are currently known, comprising about 2% of the chondrites that fall on Earth.Norton, O.R. and Chitwood, L.A. ...
– a rare form of meteorite thought to comprise only 2% of chondrites.
F
*
Fall
Autumn, also known as fall in American English and Canadian English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March ( Southe ...
– a meteorite that was seen while it fell to Earth and found.
*
Find – a meteorite that was found without seeing it fall.
* Fossil meteorite – a meteorite that was buried under layers of sediment before the start of the
Quaternary period
Period may refer to:
Common uses
* Era, a length or span of time
* Full stop (or period), a punctuation mark
Arts, entertainment, and media
* Period (music), a concept in musical composition
* Periodic sentence (or rhetorical period), a concept ...
. Some or all of the original cosmic material has been replaced by
diagenetic
Diagenesis () is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a ...
minerals.
(It is, however, not a
fossil).
* Fusion crust – a coating on meteorites that forms during their passage through the atmosphere.
G
*
Group
A group is a number of persons or things that are located, gathered, or classed together.
Groups of people
* Cultural group, a group whose members share the same cultural identity
* Ethnic group, a group whose members share the same ethnic ide ...
– a collection of five or more meteorites sharing similar characteristics.
*
Grouplet – a collection of fewer than five meteorites sharing similar characteristics.
H
*
Hammer Stone – a specific individual meteorite that has hit either a human, man-made object, and/or an animal.
*
HED – abbreviation for three basaltic achondrite groups
howardite
Howardites are achondritic stony meteorites that originate from the surface of the asteroid 4 Vesta, and as such are part of the HED meteorite clan. There are about 200 distinct members known.
Characteristics
They are a regolith breccia consisti ...
,
eucrite and
diogenite.
*
HED meteorite
HED meteorites are a clan (subgroup) of achondrite meteorites. HED stands for "howardite– eucrite– diogenite".
These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the ma ...
– a clan of basaltic achondrites.
*
Hexahedrite
Hexahedrites are a structural class of iron meteorite. They are composed almost exclusively of the nickel–iron alloy kamacite and are lower in nickel content than the octahedrites. The nickel concentration in hexahedrites is always below 5.8% and ...
– a structural class of iron meteorites having a relatively low nickel content
*
Hunter
Hunting is the human practice of seeking, pursuing, capturing, or killing wildlife or feral animals. The most common reasons for humans to hunt are to harvest food (i.e. meat) and useful animal products (fur/ hide, bone/tusks, horn/antler, ...
– a person who searches for meteorites.
I
*
Impact breccia
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.
The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of di ...
– rock composed of fragments of terrestrial, extraterrestrial or mixed origin fused by the energy of impact
*
Impactite
Impactite is rock created or modified by one or more impacts of a meteorite. Impactites are considered metamorphic rock, because their source materials were modified by the heat and pressure of the impact. On Earth, impactites consist primarily o ...
– informal term for a terrestrial rock resulting from the shocking impact of a meteor.
*
Iron–nickel alloy
An iron–nickel alloy or nickel–iron alloy, abbreviated FeNi or NiFe, is a group of alloys consisting primarily of the elements nickel (Ni) and iron (Fe). It is the main constituent of the "iron" planetary cores and iron meteorites. In chemist ...
– an alternative expression for meteoric iron.
*
Iron meteorite – a meteorite that is mainly composed of
meteoric iron.
K
*
Kakangari chondrite – a group of chondrite meteorites.
*
Kamacite – a
native metal (mineral) found in meteorites.
L
*
Lodranite – member of a small group of primitive achondrites thought to derive from deeper within the same parent body as acapulcoites
*
Lunaite – a meteorite that originated from the moon (synonym of
Lunar meteorite
A lunar meteorite is a meteorite that is known to have originated on the Moon. A meteorite hitting the Moon is normally classified as a transient lunar phenomenon.
Discovery
In January 1982, John Schutt, leading an expedition in Antarctica for ...
). Compare ''
:Meteorites found on bodies other than Earth''.
*
Lunar meteorite
A lunar meteorite is a meteorite that is known to have originated on the Moon. A meteorite hitting the Moon is normally classified as a transient lunar phenomenon.
Discovery
In January 1982, John Schutt, leading an expedition in Antarctica for ...
– a meteorite that originated from the Moon (synonym of
Lunaite). Compare ''
:Meteorites found on bodies other than Earth''.
M
*
Main group pallasite – a
pallasite belonging to the main group.
* Main mass – the largest/heaviest piece of a fragmented meteorite, typically found in a
strewn field.
*
Magmatic meteorite
*
Martian meteorite – a meteorite that originated from Mars. Compare ''
:Meteorites found on bodies other than Earth''.
*
Maskelynite
Maskelynite is a glassy material found in some meteorites and meteorite impact craters. Typical samples are similar in composition to plagioclase feldspar, and revert to that mineral when melted and recrystallized. It was named after British geolo ...
– a natural glass found in meteorites.
* Matrix – the mineral assemblage surrounding chondrules.
*
Mesosiderite
Mesosiderites are a class of stony–iron meteorites consisting of about equal parts of metallic nickel-iron and silicate. They are breccias with an irregular texture; silicates and metal occur often in lumps or pebbles as well as in fine-grained ...
– a grouping of
stony-iron meteorite
Stony-iron meteorites or siderolites are meteorites that consist of nearly equal parts of meteoric iron and silicates. This distinguishes them from the stony meteorites, that are mostly silicates, and the iron meteorites, that are mostly meteoric ...
that are breccias.
*
Meteoric iron – a
native metal found in meteorites and a mixture of different mineral phases. Compare
telluric iron
Telluric iron, also called native iron, is iron that originated on Earth, and is found in a metallic form rather than as an ore. Telluric iron is extremely rare, with only one known major deposit in the world, located in Greenland.
Introduction
Wi ...
.
*
Meteorite Observation and Recovery Program – a scientific program that was centered in Canada.
*
Meteoriticist – a scientist working on meteorites, meteors, and meteoroids.
*
Meteoritics
Meteoritics is the science that deals with meteors, meteorites, and meteoroids. It is closely connected to cosmochemistry, mineralogy and geochemistry. A specialist who studies meteoritics is known as a ''meteoriticist''.
Scientific research in ...
– the science of meteorites, meteors, and meteoroids.
*
MORP – abbreviation for
Meteorite Observation and Recovery Program.
*
Micrometeorite – microscopic meteorites derived from
Cosmic dust.
N
*
Nakhlite
Nakhlites are a group of Martian meteorites, named after the first one, Nakhla meteorite.
Nakhlites are igneous rocks that are rich in augite and were formed from basaltic magma about 1.3 billion years ago. They contain augite and olivine cryst ...
– a group of
Martian meteorites
*
Neumann lines
Neumann lines, or Neumann bands, are fine patterns of parallel lines seen in cross-sections of many hexahedrite iron meteorites in the kamacite phase, although they may appear also in octahedrites provided the kamacite phase is about 30 micrometr ...
(or Neumann bands) – a pattern of fine parallel lines seen in some iron meteorites, thought to be due to impact events on the parent body
*
Nonmagmatic meteorite – (deprecated) iron meteorites that were thought to have not formed by igneous processes.
O
* O – usually refers to
ordinary chondrite
* Observed fall – a meteorite that was seen when it fell to Earth.
*
Octahedrite
Octahedrites are the most common structural class of iron meteorites. The structures occur because the meteoric iron has a certain nickel concentration that leads to the exsolution of kamacite out of taenite while cooling.
Structure
Octahedr ...
– the most common structural class of iron meteorites.
*
Ordinary chondrite – a chondrite meteorite, where 'ordinary' means that it is the most common found
P
*
PAC Pac or PAC may refer to:
Military
* Rapid Deployment Force (Malaysia), an armed forces unit
* Patriot Advanced Capability, of the MIM-104 Patriot missile
* Civil Defense Patrols (''Patrullas de Autodefensa Civil''), Guatemalan militia and paramil ...
– abbreviation for primitive achondrite.
*
Pallasite – a class of stony–iron meteorite.
*
Panspermia
Panspermia () is the hypothesis, first proposed in the 5th century BCE by the Greek philosopher Anaxagoras, that life exists throughout the Universe, distributed by space dust, meteoroids, asteroids, comets, and planetoids, as well as by spacecr ...
– the hypothesis that life could reach other planets by the means of meteorites and/or comets.
*
Parent body – the celestial body from which originates a meteorite or a class of meteorites.
*
Petrologic type
A chondrite is a stony (non- metallic) meteorite that has not been modified, by either melting or differentiation of the parent body. They are formed when various types of dust and small grains in the early Solar System accreted to form prim ...
– a classification scheme that expresses the degree to which a meteorite has been affected by the secondary processes of thermal metamorphism and aqueous alteration on the parent asteroid.
*
Pitts grouplet
IAB meteorites are a group of iron meteorites according to their overall composition and a group of primitive achondrites because of silicate inclusions that show a strong affinity to winonaites and chondrites.
Description
The IAB meteorites are c ...
– a grouplet of meteorites that is part of the
IAB meteorites
IAB meteorites are a group of iron meteorites according to their overall composition and a group of primitive achondrites because of silicate inclusions that show a strong affinity to winonaites and chondrites.
Description
The IAB meteorites are c ...
.
*
Planetary achondrite – an achondrite that was differentiated on a planet and not a planetesimal or asteroid (See
asteroidal achondrite).
*
Plessite
Plessite is a meteorite texture consisting of a fine-grained mixture of the minerals kamacite and taenite found in the octahedrite iron meteorites. It occurs in gaps (its name is derived from the Greek "plythos" meaning "filling"according tMindat ...
– a fine grained intergrowth found in
meteoric iron consisting of
kamacite,
taenite
Taenite is a mineral found naturally on Earth mostly in iron meteorites. It is an alloy of iron and nickel, with a chemical formula of and nickel proportions of 20% up to 65%.
The name is derived from the Greek ταινία for "band, ribbon" ...
and
tetrataenite
Tetrataenite is a native metal alloy composed of chemically-ordered L10-type FeNi, recognized as a mineral in 1980. The mineral is named after its tetragonal crystal structure and its relation to the iron-nickel alloy, taenite. It is one of the m ...
lamella.
*
Presolar grains
Presolar grains are interstellar solid matter in the form of tiny solid grains that originated at a time before the Sun was formed. Presolar stardust grains formed within outflowing and cooling gases from earlier presolar stars.
The stellar nuc ...
– interstellar solid matter in the form of tiny solid grains from a time before the Sun was formed.
* Primitive meteorite
*
Primitive achondrite – a meteorite that has similarities to achondrites and chondrites.
*
Protoplanetary disk – a circumstellar disk from which all solids in the Solar System formed.
*
Pyroxene pallasite grouplet
R
* Regmaglypts – thumbprint-sized indentations in the surface of larger
meteorites formed by
ablation
Ablation ( la, ablatio – removal) is removal or destruction of something from an object by vaporization, chipping, erosive processes or by other means. Examples of ablative materials are described below, and include spacecraft material for a ...
as the meteorite passes through a planet's
atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
, probably caused by vortices of hot gas.
*
Rose-Tschermak-Brezina classification – a classification developed by
Gustav Rose
Prof Gustavus ("Gustav") Rose FRSFor HFRSE (18 March 1798 – 15 July 1873) was a German mineralogist who was a native of Berlin. He was President of the German Geological Society from 1863 to 1873.
Life
He was born in Berlin the son of pharma ...
,
Gustav Tschermak and
Aristides Brezina
Aristides Brezina (4 May 1848 – 25 May 1909) was an Austrian mineralogist born in Vienna.
In 1872 he graduated from the University of Tübingen, and afterwards taught crystallography at the University of Vienna. In 1878 he succeeded Austri ...
.
*
Rumuruti chondrite – a group of chondrites.
S
*
Shergottite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percen ...
– igneous rocks of mafic to ultramafic lithology, named after a meteorite that fell at Sherghati, India in 1865.
*
Shock stage – a measure of the degree of fracturing of the matrix of a common chondrite meteorite.
*
Shock metamorphism – the effects of shock-wave related deformation and heating during impact events.
*
Siderite – the old term for
iron meteorite.
*
Siderolite – the old term for
stony-iron meteorite
Stony-iron meteorites or siderolites are meteorites that consist of nearly equal parts of meteoric iron and silicates. This distinguishes them from the stony meteorites, that are mostly silicates, and the iron meteorites, that are mostly meteoric ...
s.
*
SNC – abbreviation for
shergottite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percen ...
,
nakhlite
Nakhlites are a group of Martian meteorites, named after the first one, Nakhla meteorite.
Nakhlites are igneous rocks that are rich in augite and were formed from basaltic magma about 1.3 billion years ago. They contain augite and olivine cryst ...
and
chassignite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percen ...
, the three main types of Martian meteorite.
*
Solar nebula – a synonym of the
protoplanetary disk.
* Spectral class –
*
Stony meteorite – a meteorite composed mostly of
silicates.
*
Stony-iron meteorite
Stony-iron meteorites or siderolites are meteorites that consist of nearly equal parts of meteoric iron and silicates. This distinguishes them from the stony meteorites, that are mostly silicates, and the iron meteorites, that are mostly meteoric ...
– a meteorite that is a mixture of
meteoric iron and
silicates.
*
Strewn field – a field of fragments from one meteorite fall.
* Structural class – a subdivision of
iron meteorites in
ataxite
Ataxites (from Greek meaning "without structure") are a structural class of iron meteorites with a high nickel content and show no Widmanstätten patterns upon etching.
Characteristics
Ataxites are composed mainly of meteoric iron, a native metal ...
s,
hexahedrite
Hexahedrites are a structural class of iron meteorite. They are composed almost exclusively of the nickel–iron alloy kamacite and are lower in nickel content than the octahedrites. The nickel concentration in hexahedrites is always below 5.8% and ...
s and
octahedrite
Octahedrites are the most common structural class of iron meteorites. The structures occur because the meteoric iron has a certain nickel concentration that leads to the exsolution of kamacite out of taenite while cooling.
Structure
Octahedr ...
s.
*
Superbolide
A bolide is normally taken to mean an exceptionally bright meteor, but the term is subject to more than one definition, according to context. It may refer to any large crater-forming body, or to one that explodes in the atmosphere. It can be a s ...
– is a bolide that reaches an apparent magnitude of −17 or brighter, which is roughly 100 times brighter than the full moon. Recent examples of superbolides include the Sutter's Mill meteorite and the Chelyabinsk meteor.
T
*
Taenite
Taenite is a mineral found naturally on Earth mostly in iron meteorites. It is an alloy of iron and nickel, with a chemical formula of and nickel proportions of 20% up to 65%.
The name is derived from the Greek ταινία for "band, ribbon" ...
– a
native metal (mineral) found in meteorites.
*
Tamdakht – a meteorite that fell near Ouarzazate, Morocco on 2008-12-20 producing a strewn field of approximately 25 km (16 mi) by 2 km (1.2 mi) and two small impact craters.
*
Tektite
Tektites (from grc, τηκτός , meaning 'molten') are gravel-sized bodies composed of black, green, brown or grey natural glass formed from terrestrial debris ejected during meteorite impacts. The term was coined by Austrian geologist Fran ...
– glassy terrestrial debris created by meteorite impacts.
*
Total known weight Total known weight (TKW), also total known mass,The British and Irish Meteorite SocietyGlossary/ref> is a term used mainly by dealers and meteorite collectors to indicate the combined weight of all known pieces from a single named meteorite. The tot ...
(TKW) – total known mass of a meteorite.
*
Trio – a grouping of three meteorites that share similar characteristics (see Grouplet).
*
Type – subdivision of meteorites. Loosely defined. Usually refers to
chondrite,
achondrite
An achondrite is a stony meteorite that does not contain chondrules. It consists of material similar to terrestrial basalts or plutonic rocks and has been differentiated and reprocessed to a lesser or greater degree due to melting and recrystalliz ...
and sometimes
primitive achondrite.
U
*
Udei Station grouplet – a grouplet of meteorites that is part of the
IAB meteorites
IAB meteorites are a group of iron meteorites according to their overall composition and a group of primitive achondrites because of silicate inclusions that show a strong affinity to winonaites and chondrites.
Description
The IAB meteorites are c ...
.
* Ungrouped – a meteorite that has not been assigned to a group or grouplet.
* Undifferentiated
*
Ureilite
V
*
Vesta – second largest asteroid in the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...
and likely source of the
HED meteorite
HED meteorites are a clan (subgroup) of achondrite meteorites. HED stands for "howardite– eucrite– diogenite".
These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the ma ...
s.
*
Volatile elements – are chemical elements that have low boiling and condensation temperatures.
W
*
Widmanstätten pattern
Widmanstätten patterns, also known as Thomson structures, are figures of long nickel–iron crystals, found in the octahedrite iron meteorites and some pallasites. They consist of a fine interleaving of kamacite and taenite bands or ribbons c ...
– a fine interleaving of kamacite and taenite bands/ribbons found in octahedrite irons and some pallasites.
*
Willamette meteorite – the largest meteorite discovered in North America, found in the
Willamette Valley of Oregon.
*
Winonaite – a type of primitive achondrite meteorite.
*
Weston meteorite
The Weston meteorite is an H4 ordinary chondrite meteorite which fell to earth above the town of Weston, Connecticut on the morning of December 14, 1807.
History
The Weston meteorite fell to earth above the town of Weston, Connecticut at approxi ...
– a meteorite which fell to earth above the town of
Weston, Connecticut
Weston is a town in Fairfield County, Connecticut, United States. The population was 10,354 at the 2020 census with the highest median household income in Connecticut. The town is served by Route 57 and Route 53, both of which run through the ...
on December 14, 1807.
References
{{meteorites
Meteorites
Geology terminology
Meteoritics
Meteoritics is the science that deals with meteors, meteorites, and meteoroids. It is closely connected to cosmochemistry, mineralogy and geochemistry. A specialist who studies meteoritics is known as a ''meteoriticist''.
Scientific research in ...