CM chondrite#Petrologic types

Meteorites mostly divide into Ordinary and 'Carbonaceous' chondrite classes; far fewer belong to lesser classes like Enstatites and Ureilites. The term 'chondrite' indicates that these contain (or may have contained) chondrules in a matrix. Chondrules are cooled droplets of minerals, predating the meteorites themselves. The term 'carbonaceous' was assigned relative to the ordinary chondrites; some Enstatite and Ureilite meteorites may have more carbon than C-chondrites.{{cite book |last1=Scott |first1=E |last2=Krot |first2=A |title=Treatise on Geochemistry|volume=1 |date=2003 |page=143 |publisher=Elsevier |isbn=0-08-043751-6}} Ch. Chondrites and their Components Still, all C-chondrites are distinguished from ordinary chondrites by a non-trace carbon content (resulting in a dark color), plus other volatiles, giving a lower density.{{cite journal |last1=Britt |first1=D |title=The porosity of dark meteorites and the structure of low-albedo asteroids |bibcode=2000Icar..146..213B |journal=Icarus |date=Jul 2000 |volume=143 |issue=1 |page=213|doi=10.1006/icar.2000.6374 }}{{cite journal |last1=Macke |first1=R |last2=Consolmagno |first2=G |last3=Britt |first3=D |title=Density, porosity, and magnetic susceptibility of carbonaceous chondrites |journal=Meteoritics & Planetary Science |date=Nov 2011 |volume=46 |issue=12 |page=1842|doi=10.1111/j.1945-5100.2011.01298.x |bibcode=2011M&PS...46.1842M |s2cid=128721593 |doi-access=free }} After the classes were devised, a more rigorous definition was found: C-chondrites contain proportionally higher magnesium than ordinary chondrites.{{cite journal |last1=Urey |first1=H |title=Criticism of Dr. B. Mason's paper on "The origin of meteorites" |bibcode=1961JGR....66.1988U |journal= Journal of Geophysical Research|date=Jun 1961 |volume=66 |issue=6 |page=1988|doi=10.1029/JZ066i006p01988 }}{{cite journal |last1=Ahrens |first1=L |title=Si-Mg fractionation in chondrites |bibcode=1964GeCoA..28..411A |journal=Geochimica et Cosmochimica Acta |date=1964 |volume=28 |issue=4 |page=411|doi=10.1016/0016-7037(64)90115-2 }}{{cite journal |last1=Ahrens |first1=L |title=Observations on the Fe-Si-Mg relationship in chondrites |bibcode=1965GeCoA..29..801A |journal=Geochimica et Cosmochimica Acta |date=1965 |volume=29 |issue=7 |page=801|doi=10.1016/0016-7037(65)90032-3 }}

The C-chondrites subdivide into CI, CM, CO, CV, CK, CR, and lesser groups (CH, CB, and ungrouped C-meteorites). Specimens are formed into groups by their petrological and chemical qualities, and the group named for a salient example. These include the CI (Ivuna-like), CM (Mighei-like), CO (Ornans-like), etc. The CM group most resembles the CI and CO chondrites; a CM–CO is sometimes described.{{cite journal |last1=Kallemeyn |first1=G |last2=Wasson |first2=J |title=The compositional classification of chondrites-I. The carbonaceous chondrite groups |journal=Geochimica et Cosmochimica Acta |date=1981 |volume=45 |issue=7 |page=1217|doi=10.1016/0016-7037(81)90145-9 |bibcode=1981GeCoA..45.1217K }}{{cite book |last1=Weisberg |first1=M |bibcode=1981GeCoA..45.1217K |last2=McCoy |first2=T |last3=Krot |first3=A |title=Meteorites and the Early Solar System II |journal=Geochimica et Cosmochimica Acta |volume=45 |issue=7 |date=2006 |publisher=University of Arizona Press |location=Tucson |page=19 |chapter=Systematics and Evaluation of Meteorite Classification|doi=10.1016/0016-7037(81)90145-9 }}{{cite web |title=CM-CO clan chondrites |url=https://www.lpi.usra.edu/meteor/metbull.php?sea=&sfor=names&stype=contains&lrec=50&categ=CM-CO+clan+chondrites&srt= |website=Meteoritical Bulletin: Search the Database |publisher=The Meteoritical Society |accessdate=10 Sep 2019}} All three groups contain clearly anomalous ⁵⁰Ti and ⁵⁴Cr isotopes.{{cite journal |last1=Trinquier |first1=A |last2=Elliott |first2=T |last3=Ulfbeck |first3=D |last4=Coath |first4=C |last5=Krot |first5=A |last6=Bizzarro |first6=M |title=Origin of Nucleosynthetic Isotope Heterogeneity in the Solar Protoplanetary Disk |doi=10.1126/science.1168221 |pmid=19372428 |journal=Science |date=17 Apr 2009 |volume=324 |issue=5925 |pages=374–6 |bibcode=2009Sci...324..374T |s2cid=6120153 }}{{cite journal |last1=Qin |first1=L |last2=Rumble |first2=D |last3=Alexander |first3=C |last4=Carlson |first4=R |last5=Jenniskens |first5=P |last6=Shaddad |first6=M |title=The chromium isotopic composition of Almahata Sitta |bibcode=2010LPI....41.1910Q |journal=Meteoritics & Planetary Science |date=2010 |volume=45 |issue=1533 |page=1771|doi=10.1111/j.1945-5100.2010.01109.x |s2cid=55170869 |doi-access=free }}

Though the C-chondrites are far rarer than ordinary chondrites, the CM group is "the most abundant type of" them.{{cite journal |last1=McSween |first1=H |title=Alteration in CM carbonaceous chondrites inferred from modal and chemical variations in matrix |doi=10.1016/0016-7037(79)90024-3 |journal=Geochimica et Cosmochimica Acta |date=1979 |volume=43 |issue=11 |page=1761|bibcode=1979GeCoA..43.1761M }}{{cite journal |last1=Howard |first1=K |last2=Benedix |first2=G |last3=Bland |first3=P |last4=Cressey |first4=G |title=Modal mineralogy of CM chondrites by X-ray Diffraction (PSR-XRD) |doi=10.1111/j.1945-5100.2004.tb00046.x |journal=Geochimica et Cosmochimica Acta |date=2011 |volume=75 |page=2735|doi-access=free }} The latest Catalogue of Meteorites (5th edition, 2000) gives 15 CM falls (observed entries, then recoveries), and 146 finds (meteorites with entries unobserved, possibly ancient). By contrast, the next highest are the COs- 5 falls, 80 finds listed. These are in a class of 36 C-chondrite falls, 435 finds. If the CMs and COs are taken to be a clan, its dominance is even higher.{{cite book |last1=Grady |first1=M |title=The Catalogue of Meteorites |date=2000 |publisher=Cambridge University Press |location=Cambridge |isbn=0-521-66303-2}}

C-chondrites in general, and CM chondrites among them, have low densities for meteorites. CMs are slightly more dense (~2.1 gram/cc) than the CIs, but less dense than CO and other C-chondrites.{{cite journal |last1=Britt |first1=D |last2=Consolmagno |first2=G |title=Stony meteorite porosities and densities: A review of the data through 2001|doi=10.1111/j.1945-5100.2003.tb00305.x |journal=Meteoritics & Planetary Science |date=August 2003 |volume=38 |issue=8 |page=1161|bibcode=2003M&PS...38.1161B |s2cid=55612044 |doi-access= }}{{cite journal |last1=Carry |first1=B |title=Density of asteroids |bibcode=2012P&SS...73...98C |journal=Planetary and Space Science |date=2012 |volume=73 |issue=1 |page=98|arxiv=1203.4336 |doi=10.1016/j.pss.2012.03.009 |s2cid=119226456 }} This is due to a combination of brecciation (rock lithified from fragments of prior rocks){{cite conference |last1=Bischoff |first1=A |last2=Ebert |first2=S |last3=Metzler |first3=K |last4=Lentfort |first4=S |title=Breccia Classification of CM Chondrites |bibcode=2017LPICo1987.6089B |conference=80th Meteoritical Society |date=2017 |issue=1987}} including porosities and inherently light constituent materials (see chemistry, below). (Rare unbrecciated CMs include Y-791198 and ALH81002.{{cite conference |last1=Chizmadia |first1=L |last2=Brearley |first2=A |title=Aqueous Alteration Of Carbonaceous Chondrites: New Insights From Comparative Studies Of Two Unbrecciated CM2 Chondrite, Y-791198 And ALH81002 |bibcode=2004LPI....35.1753C |conference=LPS XXXV |date=2004 |issue=1753}})

Based primarily on petrology, early scientists attempted to quantify different meteorites. Rose ("kohlige meteorite"),{{cite book |last1=Rose |first1=G |title=Physik. Abhandl. Akad. Wiss. |date=1863 |location=Berlin |page=23}} then Tschermak devised early taxonomies.{{cite journal|last1=Tschermak|first1=G|title=Beitrag zur Classification der Meteoriten|journal=Math. -Naturw. Cl.|publisher=Sitzber. Akad. Wiss.|date=1883|volume=85|issue=1|pages=347–71}} In the 1904 scheme of Brezina, today's CM chondrites would be "K" ("coaly chondrites").{{cite journal |last1=Brezina |first1=A |title=The Arrangement of Collections of Meteorites |jstor=983506 |journal=Proc. Am. Philos. Soc. |date=1904 |volume=43 |issue=176 |pages=211–247 }} Wiik published the first recognizably modern system in 1956, dividing meteorites into Type I, II, and III. CMs fell within Wiik's Type II.{{cite journal |last1=Wiik |first1=H |title=The chemical composition of some stony meteorites |bibcode=1956GeCoA...9..279W |journal=Geochimica et Cosmochimica Acta |date=1956 |volume=9 |issue=5 |page=279|doi=10.1016/0016-7037(56)90028-X }}

The CM chondrites are essentially all Type 2 in the petrographic scale of Van Schmus and Wood 1967; by that time, CI and CM recoveries were enough to define the 'left' (aqueous alteration) end of the scale. (CI chondrites, the Van Schmus Wood Type 1, is equivalent to Wiik's Type I, etc.) The types 4 through 6 indicate increasing thermal alteration; Type 3 is assumed to be unaltered.{{cite journal |last1=Van Schmus |first1=W |last2=Wood |first2=J |title=A chemical-petrologic classification for the chondritic meteorites |bibcode=1967GeCoA..31..747V |journal=Geochimica et Cosmochimica Acta |date=1967 |volume=31 |issue=5 |page=747|doi=10.1016/S0016-7037(67)80030-9 }}

Van Schmus, Wood 1967; Sears, Dodd 1988; Brearley, Jones 1998; Weisberg 2006

The modern groups 'V' and 'O' were named by Van Schmus in 1969 as divisions of Type 3, as 'subclass {{not a typo|C3V}}' and '{{not a typo|C3O}}'.{{cite book|editor-last1=Millman|editor-first1=P.|title=Meteorite Research |date=1969 |publisher=D. Reidel Publishing Company |location=Dordrecht |isbn=978-94-010-3413-5 |page=480 |chapter=Mineralogical, Petrology, and Classification of Types 3 and 4 Carbonaceous Chondrites}} Wasson then added C2M in 1974; since then, C2Ms have generally been shortened to simply 'CM', as have the other groups.{{cite book |last1=Wasson |first1=J |title=Meteorites: Classification and Properties |date=1974 |publisher=Springer-Verlag |location=New York |isbn=978-3-642-65865-5}}

After Weisberg et al. 2006, Giese et al. 2019{{cite journal |last1=Giese |first1=C Ten Kate I Plumper O King H Lenting C Liu Y Tielens A |title=The evolution of polycyclic aromatic hydrocarbons under simulated inner asteroid conditions |doi=10.1111/maps.13359 |journal=Meteoritics & Planetary Science |date=Jul 2019 |volume=54 |issue=9 |page=1930|bibcode=2019M&PS...54.1930G |doi-access=free |hdl=1887/84978 |hdl-access=free }} Note: lone CV2 specimen, Mundrabilla 012{{cite web |title=Meteoritical Bulletin: Entry for Mundrabilla 012 |url=https://www.lpi.usra.edu/meteor/metbull.php?code=16863 |website=Meteoritical Bulletin |publisher=The Meteoritical Society |accessdate=14 Sep 2019}}{{cite web |title=Mundrabilla 012 meteorite, Mundrabilla Roadhouse, Dundas Shire, Western Australia, Australia |url=https://www.mindat.org/loc-297049.html |website=Mindat.org |accessdate=14 Sep 2019}}

As Type 2 meteorites, CM chondrites have some remaining chondrules; others have been modified or dissolved by water. COs have more chondrules; CIs have either trace outlines of former chondrules ("pseudomorphs") or, some have argued, never contained any chondrules at all. Many CM chondrules are surrounded by either rims of accessory minerals, or haloes of water-altered chondrule material.{{cite conference |last1=Bunch |first1=T |last2=Chang |first2=S |title=Carbonaceous chondrite (CM) phyllosilicates: condensation or alteration origin? |bibcode=1978LPI.....9..134B |conference=Lunar and Planetary Science IX |date=1978 |page=134}}{{cite book |last1=Metzler |first1=K |last2=Bischoff |first2=A |title=Chondrules and the Protoplanetary Disk, NASA-CR-197121 |date=Jan 1994 |page=23 |chapter=Constraints on chondrule agglomeration from fine-grained chondrule rims}}

The chondrules of CM chondrites, though fewer, are larger than in COs. While CM chondrules are smaller than average in diameter (~300 micrometer), CO chondrules are exceptionally small (~170 um).{{cite journal |last1=Rubin |first1=A |title=Size-frequency distributions of chondrules in CO3 chondrites |bibcode=1989Metic..24..179R |journal=Meteoritics |date=Sep 1989 |volume=24 |issue=3 |page=179|doi=10.1111/j.1945-5100.1989.tb00960.x }}{{cite journal |last1=Choe |first1=W |last2=Huber |first2=H |last3=Rubin |first3=A |last4=Kallemeyn |first4=G |last5=Wasson |first5=J |title=Compositions and taxonomy of 15 unusual carbonaceous chondrites |bibcode=2010M&PS...45..531C |journal=Meteoritics & Planetary Science |date=Apr 2010 |volume=45 |issue=4 |page=531|doi=10.1111/j.1945-5100.2010.01039.x |s2cid=16839084 |doi-access=free }} This may be a survivor bias: consider that the water which dissolves CM chondrules successfully eliminates those which are already small, while those which were large may remain to be observed, though with less of the original material.{{cite journal |last1=Rubin |first1=A |title=Correlated petrologic and geochemical characteristics of CO3 chondrites |bibcode=1998M&PS...33..385R |journal=Meteoritics & Planetary Science |date=May 1998 |volume=33 |issue=2 |page=385|doi=10.1111/j.1945-5100.1998.tb01644.x |s2cid=129404145 |doi-access=free }} Similarly, CMs contain minor CAIs (calcium–aluminium rich inclusions).{{cite journal |last1=Rubin |first1=A |title=Petrography of refractory inclusions in CM2.6 QUE 97990 and the origin of melilite-free spinel inclusions in CM chondrites |bibcode=2007M&PS...42.1711R |journal=Meteoritics & Planetary Science |date=Oct 2007 |volume=42 |issue=10 |page=1711|doi=10.1111/j.1945-5100.2007.tb00532.x |doi-access=free }}{{cite journal |last1=Hezel |first1=D |last2=Russell |first2=S |last3=Ross |first3=A |last4=Kearsley |first4=A |title=Modal abundances of CAIs: Implications for bulk chondrite element abundances and fractionations |bibcode=2008M&PS...43.1879H |journal=Meteoritics & Planetary Science |date=2008 |volume=43 |issue=11 |page=1879|arxiv=0810.2174 |doi=10.1111/j.1945-5100.2008.tb00649.x |s2cid=119289798 }}

The matrix of CMs (ground material, between chondrules) has been described as "sponge" or "spongy."

Grains of olivine and pyroxene silicates, too, are fewer in CM meteorites than COs, but more than CIs. As with chondrules, these are water-susceptible, and follow the water progression of the petrographic scale. So, too, do grains of free metal. CO meteorites contain higher levels of free metal domains, where CIs have mostly oxidized theirs; CMs are in between.{{cite journal |last1=Barber |first1=D |title=The Matrix of C2 and C3 Carbonaceous Chondrites |bibcode=1977Metic..12..172B |journal=Meteoritics |date=1977 |volume=12 |page=172}}{{cite journal |last1=Barber |first1=D |title=Matrix phyllosilicates and associated minerals in C2M carbonaceous chondrites |bibcode=1981GeCoA..45..945B |journal=Geochimica et Cosmochimica Acta |date=1981 |volume=45 |issue=6 |page=945|doi=10.1016/0016-7037(81)90120-4}}

Both free metal, and grains of olivine/pyroxene, have been largely or predominantly altered to matrix materials.{{cite journal |last1=Wood |first1=J |title=Chondrites: Their metallic minerals, thermal histories, and parent planets |journal=Icarus |date=1967 |volume=6 |issue=1 |pages=1–49 |doi=10.1016/0019-1035(67)90002-4|bibcode=1967Icar....6....1W }} A CM meteorite will consist of more matrix than a CO, but less than a CI (which are essentially all matrix, per Van Schmus & Wood 1967).{{cite journal |last1=Wood |first1=J |title=Olivine and pyroxene compositions in type II carbonaceous chondrites |bibcode=1967GeCoA..31.2095W |journal=Geochimica et Cosmochimica Acta |date=Oct 1967 |volume=31 |issue=10 |page=2095|doi=10.1016/0016-7037(67)90144-5 }}

In 1860, Wohler presciently or coincidentally identified matrix as serpentinite.{{cite journal |last1=Wöhler |first1=F |journal=Sitzungsber. Akad. Wissensch. |date=1860 |volume=41 |page=565}} Fuchs et al. 1973, unable to identify the constituent phyllosilicates, gave matrix as "poorly characterized phase" (PCP).{{cite journal |last1=Fuchs |first1=L |last2=Olsen |first2=E |last3=Jensen |first3=K |title=Mineralogy, mineral-chemistry, and composition of the Murchison (C2) meteorite |url=https://archive.org/details/mineralogyminera0000fuch |url-access=registration |journal=Smithsonian Contributions to the Earth Sciences |date=1973 |issue=10 |pages=[https://archive.org/details/mineralogyminera0000fuch/page/1 1]–39 |doi=10.5479/si.00810274.10.1}} Cronstedtite was published by Kurat and Kracher in 1975.{{cite journal |last1=Kurat |first1=G |last2=Kracher |first2=A |title=Preliminary report on the Cochabamba carbonaceous chondrite |journal=Meteoritics |date=Dec 1975 |volume=10 |pages=432–433|bibcode=1975Metic..10..432K }}

Tomeoka and Buseck, identifying cronstedtite and tochilinite in 1985, gave matrix material as “FESON” (Fe–Ni–S–O layers), as well as the backronym “partly characterized phase” for “PCP.”{{cite journal |last1=Tomeoka |first1=K |last2=Buseck |first2=P |title=Indicators of aqueous alteration in CM carbonaceous chondrites |journal=Geochimica et Cosmochimica Acta |date=1985 |volume=49 |issue=10 |pages=2149–2163 |doi=10.1016/0016-7037(85)90073-0}} Later authors would use the term TCI, tochilinite-cronstedtite intergrowths. Less common phyllosilicates include chlorite, vermiculite, and saponite.{{cite journal |last1=Barber |first1=D |title=Phyllosilicates and other layer-structured minerals in stony meteorites |journal=Clay Minerals |date=Dec 1985 |volume=20 |issue=4 |pages=415–454|doi=10.1180/claymin.1985.020.4.01 |s2cid=129110766 }}{{cite book |last1=Lauretta |first1=D |last2=McSween |first2=H |title=Meteorites And The Early Solar System II |date=2006 |publisher=University of Arizona Press |location=Tucson |isbn=9780816525621 |page=588 |chapter=The Action of Water}}

The CM group is both numerous and diverse. Multiple attempts have been made to subdivide the group beyond the Van Schmus–Wood typing. McSween 1979 was an early proposal.{{cite journal |last1=McSween |first1=H |title=Alteration in CM carbonaceous chondrites inferred from modal and chemical variations in matrix |bibcode=1979GeCoA..43.1761M |journal=Geochimica et Cosmochimica Acta |date=1979 |volume=43 |issue=11 |page=1761|doi=10.1016/0016-7037(79)90024-3 }} After him, these add a suffix after the petrologic type, with 'CM2.9' referring to less-altered, CO-like specimens, and 'CM2.0' being more-altered, CI-like meteorites. (As of recently, no true 2.9 specimens have been catalogued.)

McSween 1979 graded the amount of matrix versus total amount, and the depletion of iron in the matrix, to quantify higher degrees of alteration.

Browning et al. 1996 devised a formula ("MAI," Mineralogical Alteration Index), quantified the amount of unaltered silicate grains, and graded the alteration level of chondrules to quantify alteration.{{cite journal |last1=Browning |first1=L |last2=McSween |first2=H |last3=Zolensky |first3=M |title=Correlated alteration effects in CM carbonaceous chondrites |bibcode=1996GeCoA..60.2621B |journal=Geochimica et Cosmochimica Acta |date=1996 |volume=60 |issue=14 |page=2621|doi=10.1016/0016-7037(96)00121-4 }}

Rubin et al. 2007 added measurement of carbonates, with more dolomite and less calcite indicating higher alteration.{{cite journal |last1=Rubin |first1=A |last2=Trigo-Rodriguez |first2=J |last3=Huber |first3=H |last4=Wasson |first4=J |title=Progressive aqueous alterations of CM carbonaceous chondrites |bibcode=2007GeCoA..71.2361R |journal=Geochimica et Cosmochimica Acta |date=2007 |volume=71 |issue=9 |page=2361|doi=10.1016/j.gca.2007.02.008 }}

Howard et al. 2009, 2011 measured total abundance of phyllosilicates to quantify alteration.{{cite journal |last1=Howard |first1=K |last2=Benedix |first2=G |last3=Bland |first3=P |last4=Cressey |first4=G |title=Modal mineralogy of CM2 chondrites by X-ray diffraction (PSD-XRD). Part 1: Total phyllosilicate abundance and the degree of aqueous alteration |bibcode=2009GeCoA..73.4576H |journal=Geochimica et Cosmochimica Acta |date=Aug 2009 |volume=73 |issue=15 |page=4576|doi=10.1016/j.gca.2009.04.038 }}

Alexander et al. 2012, 2013 measured deuterium level, C/H, and nitrogen isotopes to quantify alteration.{{cite conference |last1=Alexander |first1=C |last2=Bowden |first2=R |last3=Fogel |first3=M |last4=Howard |first4=K |last5=Greenwood |first5=R |title=The Classification of CM and CR Chondrites Using Bulk H Abundances and Isotopes |conference=43rd LPSC |date=Mar 2012 |issue=1659}}{{cite journal |last1=Alexander |first1=C |last2=Howard |first2=K |last3=Bowden |first3=R |last4=Fogel |first4=M |title=The classification of CM and CR chondrites using bulk H, C N abundances and isotopic compositions |journal=Geochimica et Cosmochimica Acta |date=2013 |bibcode=2013GeCoA.123..244A|volume=123 |page=244|doi=10.1016/j.gca.2013.05.019 }}

This line of inquiry continues, as the systems have some disagreement on specimens. Murchison is consistently ranked as low-alteration, but authors differ on some more-altered meteorites.

CM–CO

• Paris – described as "the least altered CM chondrite so far"{{cite journal |last1=Hewins |first1=R |last2=Bourot-Denise |first2=M |display-authors=et al |title=The Paris meteorite, the least altered CM chondrite so far |bibcode=2014GeCoA.124..190H |journal=Geochimica et Cosmochimica Acta |date=Jan 2014 |volume=124 |page=190 |doi=10.1016/j.gca.2013.09.014}} "that bridges the gap between CMs and COs"{{cite journal |last1=Bourot-Denism |first1=M |last2=Zanda |first2=B |last3=Marrocchi |first3=Y |last4=Greenwood |first4=R |last5=Pont |first5=S |title=Paris: The slightly altered, slightly metamorphosed CM that bridges the gap between CMs and COs |bibcode=2010LPI....41.1683B |journal=41st LPSC |date=Mar 2010 |issue=1683|pages=1683 }}
• ALHA77307
• Adelaide
• Acfer 094
• MAC87300, MAC88107

CM–CI

• Bells
• EET83334
• ALH88045
• Tagish Lake
• Dhofar 225

The CI and CM chondrites are the "water rich" meteorites,{{cite journal |last1=Ostrowski |first1=D |last2=Lacy |first2=C |last3=Gietzen |first3=K |last4=Sears |first4=D |title=IRTF spectra for 17 asteroids from the C and X complexes: A discussionof continuum slopes and their relationships to C chondrites and phyllosilicates |journal=Icarus |date=Feb 2011 |volume=212 |issue=2 |pages=682–696|doi=10.1016/j.icarus.2011.01.032 |bibcode=2011Icar..212..682O }}{{cite journal |last1=Alexander |first1=C |last2=McKeegan |first2=K |last3=Altwegg |first3=K |author3-link=Kathrin Altwegg|title=Water Reservoirs in Small Planetary Bodies: Meteorites, Asteroids, and Comets |journal=Space Science Reviews |date=Feb 2018 |volume=214 |issue=1 |page=36|doi=10.1007/s11214-018-0474-9 |pmid=30842688 |pmc=6398961 |bibcode=2018SSRv..214...36A }}{{cite journal |last1=Trigo-Rodríguez |first1=J |last2=Rimola |first2=A |last3=Tanbakouei |first3=S |last4=Cabedo Soto |first4=V |last5=Lee |first5=M |title=Accretion of water in carbonaceous chondrites: current evidence and implications for the delivery of water to early earth |journal=Space Science Reviews |date=Feb 2019 |volume=215 |issue=1 |pages=18 |bibcode=2019SSRv..215...18T |arxiv=1902.00367 |doi=10.1007/s11214-019-0583-0 |s2cid=119196857 }} CMs having 3–14 wt% water.{{cite journal |last1=D’Angelo |first1=M |last2=Cazaux |first2=S |last3=Kamp |first3=I |last4=Thi |first4=W |last5=Woitke |first5=P |title=On water delivery in the inner solar nebula: Monte Carlo simulations of forsterite hydration |journal=Astronomy & Astrophysics |date=Feb 2019 |volume=622 |page=A208 |doi=10.1051/0004-6361/201833715|bibcode=2019A&A...622A.208D |arxiv=1808.06183 |s2cid=55659350 }} Water is contained in tochilinite,{{cite conference |last1=Gooding |first1=J |last2=Zolensky |first2=M |title=Thermal Stability Of Tochilinite |conference=LPSC XVIII |date=Mar 1987 |issue=343}}{{cite conference |last1=Nakamura |first1=T |last2=Matsuoka |first2=M |last3=Yamashita |first3=S |last4=Sato |first4=Y |last5=Mogi |first5=K |last6=Enokido |first6=Y |last7=Nakata |first7=A |last8=Okumura |first8=S |last9=Furukawa |first9=Y |last10=Zolensky |first10=M |title=Mineralogical, Spectral, and Compositional Changes During Heating of Hydrous Carbonaceous Chondrites |conference=Lunar and Planetary Science XLVIII |date=Mar 2017 |issue=1954}} cronstedtite,{{cite journal |last1=Beck |first1=P |last2=Quirico |first2=E |last3=Montes-Hernandez |first3=G |last4=Bonal |first4=L |last5=Bollard |first5=J |last6=Orthous-Daunay |first6=F |last7=Howard |first7=K |last8=Schmitt |first8=B |last9=Brissaud |first9=O |last10=Deschamps |first10=F |last11=Wunder |first11=B |last12=Guillot |first12=S |title=Hydrous mineralogy of CM and CI chondrites from infrared spectroscopy and their relationship with low albedo asteroids |journal=Geochimica et Cosmochimica Acta |date=2010 |volume=74 |issue=16 |pages=4881–4892|doi=10.1016/j.gca.2010.05.020 |bibcode=2010GeCoA..74.4881B }} and others.{{cite journal |last1=Buseck |first1=P |last2=Hua |first2=X |title=Matrices Of Carbonaceous Chondrite Meteorites |journal=Annu. Rev. Earth Planet. Sci. |date=1993 |volume=21 |pages=255–305|doi=10.1146/annurev.ea.21.050193.001351 |bibcode=1993AREPS..21..255B }}{{cite journal |last1=Takir |first1=D |last2=Emery |first2=J |last3=Mcsween |first3=H |last4=Hibbitts |first4=C |last5=Clark |first5=R |last6=Pearson |first6=N |last7=Wang |first7=A |title=Nature and degree of aqueous alteration in CM and CI carbonaceous chondrites |journal=Meteoritics & Planetary Science |date=Sep 2013 |volume=48 |issue=9 |pages=1618–1637|bibcode=2013M&PS...48.1618T |doi=10.1111/maps.12171 |s2cid=129003587 |doi-access=free }}

This water, not comets,{{cite journal |last1=Morbidelli |first1=A. |last2=Chambers |first2=J |last3=Lunine |first3=Jonathan I. |last4=Petit |first4=Jean-Marc |last5=Robert |first5=F. |last6=Valsecchi |first6=G. |last7=Cyr |first7=K. |title=Source regions and timescales for the delivery of water to the Earth |journal=Meteoritics & Planetary Science |date=2000 |volume=35 |issue=6 |pages=1309–20|doi=10.1111/j.1945-5100.2000.tb01518.x |bibcode=2000M&PS...35.1309M |doi-access=free }}{{cite journal |last1=Hallis |first1=L |title=D/H ratios of the inner Solar System |journal= Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences|date=28 May 2017 |volume=375 |issue=2094|pages=20150390 |bibcode=2017RSPTA.37550390H |doi=10.1098/rsta.2015.0390 |pmid=28416726 |pmc=5394254 }} was the likely origin of Earth's oceans via isotope tracing (primarily deuterium, but also others).{{cite journal |last1=Alexander |first1=C |last2=Bowden |first2=R |last3=Fogel |first3=M |last4=Howard |first4=K |last5=Herd |first5=C |last6=Nittler |first6=L |title=The Provenances of Asteroids, and Their Contributions to the Volatile Inventories of the Terrestrial Planets |journal=Science |date=10 Aug 2012 |volume=337 |issue=6095 |pages=721–723|doi=10.1126/science.1223474 |pmid=22798405 |bibcode=2012Sci...337..721A |s2cid=206542013 |doi-access=free }}

Fluid inclusions containing meteorite water have long been reported;{{cite book |editor-last=Roedder |editor-first=E |last1=Yasinskaya |first1=A |title=Fluid Inclusion Research- Proc. COFFI 2 |date=1969 |pages=149–153 |chapter=Inclusions in stony meteorites}}{{cite journal |last1=Fieni |first1=C |last2=Bourot-Denise |first2=M |last3=Pellas |first3=P |last4=Touret |first4=J |title=Aqueous fluid inclusions in feldspars and phosphates from Peetz Chondrite |journal=Meteoritics |date=1978 |volume=13 |pages=460–461|bibcode=1978Metic..13..460F }}{{cite journal |last1=Mattey |first1=D |last2=Pillinger |first2=C |last3=Fallick |first3=A |title=H isotopic composition of water in fluid inclusions in the Peetz L6 Chondrite |journal=Meteoritics & Planetary Science |date=1983 |volume=18 |page=348}} however, these claims were doubted due to, e. g., contamination by cutting fluids during sectioning.{{cite journal |last1=Rudnick |first1=R |last2=Ashwal |first2=L |last3=Henry |first3=D |last4=Gibson |first4=E |title= Fluid inclusions in stony meteorites—A cautionary note|journal= Journal of Geophysical Research: Solid Earth|date=Mar 1984 |volume=90 Suppl |issue=669|pages=C669–75 |doi=10.1029/jb090is02p0c669 |pmid=11542002 }}{{cite journal |last1=Bodnar |first1=R |last2=Zolensky |first2=M |title=Title: Fluid Inclusions in Meteorites: Are They Useful, and Why are They So Hard to Find? |journal=Meteoritics & Planetary Science |date=2000 |volume=35 |issue=5 |page=A29}} More modern claims have taken steps such as waterless preparation.{{cite journal |last1=Saylor |first1=J |last2=Zolensky |first2=M |last3=Bodnar |first3=R |last4=Le |first4=L |last5=Schwandt |first5=C |title=Fluid Inclusions In Carbonaceous Chondrites |journal=LPS Xxxii |date=Mar 2001 |issue=1875|pages=1875 |bibcode=2001LPI....32.1875S }}{{cite journal |last1=Zolensky |first1=M |title=Liquid Water in Asteroids: Evidence from Fluid Inclusions in Meteorites |journal=Astrobiology Science Conference 2010 |volume=1538 |date=2010 |issue=5278|pages=5278 |bibcode=2010LPICo1538.5278Z }}{{cite journal |last1=Yurimoto |first1=H |last2=Itoh |first2=S |last3=Zolensky |first3=M |title=Isotopic compositions of asteroidal liquid water trapped in fluid inclusionsof chondrites |journal=Geochemical Journal |date=Oct 2014 |volume=48 |issue=6 |pages=549–560|doi=10.2343/geochemj.2.0335 |bibcode=2014GeocJ..48..549Y |doi-access=free |hdl=2115/57641 |hdl-access=free }}

Carbonaceous chondrites, as the name suggests, contain appreciable carbon compounds.{{cite journal |last1=Pearson |first1=V |last2=Sephton |first2=M |last3=Franchi |first3=I |last4=Gibson |first4=J |last5=Gilmour |first5=I |title=Carbon and nitrogen in carbonaceous chondrites: Elemental abundances and stable isotopic compositions |bibcode=2006M&PS...41.1899P |journal=Meteoritics & Planetary Science |date=Jan 2010 |volume=41 |issue=12 |page=1899|doi=10.1111/j.1945-5100.2006.tb00459.x |s2cid=59383820 }} These include native carbon, simple compounds like metal carbides and carbonates, organic chains, and polycyclic aromatic hydrocarbons (PAHs).{{cite journal |last1=Hayes |first1=J |title=Organic constituents of meteorites—a review |journal=Geochimica et Cosmochimica Acta |date=Sep 1967 |volume=31 |issue=9 |pages=1395–1440 |doi=10.1016/0016-7037(67)90019-1}}{{cite journal |last1=Botta |first1=O |last2=Bada |first2=J |s2cid=93938395 |title=Extraterrestrial Organic Compounds in Meteorites |journal=Surveys in Geophysics |date=Jan 2002 |volume=23 |issue=5 |pages=411–67 |doi=10.1023/A:1020139302770|bibcode=2002SGeo...23..411B }}

The elemental abundances of some C-chondrite groups (with the obvious exception of hydrogen, helium, and some other elements, see below){{cite journal |last1=Holweger |first1=H |title=The solar Na/Ca and S/Ca ratios: A close comparison with carbonaceous chondrites |doi=10.1016/0012-821X(77)90116-9 |journal=Earth and Planetary Science Letters |date=Feb 1977 |volume=34 |issue=1 |page=152|bibcode=1977E&PSL..34..152H }}{{cite journal |last1=Anders |first1=E |last2=Ebihara |first2=M |title=Solar-system abundances of the elements |bibcode=2014pacs.book...15P |journal=Geochimica et Cosmochimica Acta |date=Nov 1982 |volume=46 |issue=11 |page=2363|doi=10.1016/0016-7037(82)90208-3 }} have long been known to resemble solar abundance values.{{cite journal |last1=Suess |first1=H |s2cid=11969464 |title=Die kosmische häufigkeit der chemischen elemente |doi=10.1007/BF02149939 |pmid=18146573 |journal=Experientia |date=1949 |volume=5 |issue=7 |pages=266–70 }}{{cite journal |last1=Suess |first1=H Urey H |title=Abundances of the Elements |doi=10.1103/RevModPhys.28.53 |journal=Rev. Mod. Phys. |date=Jan 1956 |volume=28 |issue=1 |page=53|bibcode=1956RvMP...28...53S }}{{cite journal |last1=Asplund |first1=M |last2=Grevesse |first2=N |last3=Sauval |first3=AJ |last4=Scott |first4=P |title=The chemical composition of the Sun |doi=10.1146/annurev.astro.46.060407.145222 |journal=Annual Review of Astronomy & Astrophysics |date=2009 |volume=47 |issue=1 |pages=481–522 |bibcode=2009ARA&A..47..481A |arxiv=0909.0948 |s2cid=17921922 }} The CI chondrites, in particular, correspond "quite closely, more so than does any other type of meteoric or terrestrial matter";{{cite journal |last1=Anders |first1=E |s2cid=122077103 |title=Origin, age, and composition of meteorites |doi=10.1007/BF00177954 |journal=Space Science Reviews |date=Dec 1964 |volume=3 |issue=5–6 |page=5|bibcode=1964SSRv....3..583A }} called "somewhat miraculous". Of course, only gas giant planets have the mass to retain, explicitly, hydrogen and helium. This extends to most noble gases, and to lesser amounts the elements N, O and C, the atmophiles. Other elements- volatiles and refractories- have correspondences between CI chondrites and the solar photosphere and solar wind such that the CI group is used as a cosmochemical standard.{{cite book |editor-last1=Goswami |editor-first1=A |editor-last2=Eswar Reddy |editor-first2=B|title=Principles and Perspectives in Cosmochemistry: Lecture Notes of the Kodai School on 'Synthesis of Elements in Stars' held at Kodaikanal Observatory, India, April 29 – May 13, 2008 |date=2010 |publisher=Springer-Verlag |location=Heidelberg |isbn=978-3-642-10351-3 |page=379 |chapter=Solar system abundances of the elements}}{{cite book |last1=Davis |first1=A |title=Planets, Asteroids, Comets and The Solar System, Treatise on Geochemistry, Vol. 2 |date=2014 |publisher=Elsevier |isbn=978-0080999432 |page=21 |edition=2nd |chapter=Solar System Abundances of the Elements}} As the Sun is 99% of the mass of the Solar System, knowing the solar abundance is the starting point for any other part or process of this System.{{cite journal |last1=Russell |first1=C |title=Foreword |journal=Space Science Reviews |date=Jan 2003 |volume=105 |issue=3 |pages=vii}} Special Issue: The Genesis Discovery Mission

The solar correspondence is similar but weaker in CM chondrites. More-volatile elements have been somewhat depleted relative to the CIs, and more-refractory elements somewhat enriched.

A small amount{{cite conference |last1=Leitner |first1=J |last2=Hoppe |first2=P |last3=Metzler |first3=K |last4=Haenecour |first4=P |last5=Floss |first5=C |last6=Vollmer |first6=C |title=The Presolar Grain Inventory Of CM Chondrites |bibcode=2015LPICo1856.5178L |conference=78th Meteoritical Society Meeting |date=2015 |issue=5178}} of meteorite materials are small presolar grains (PSGs).{{cite journal |last1=Huss |first1=G |last2=Meshik |first2=A |last3=Smith |first3=J |last4=Hohenberg |first4=C |title=Presolar diamond, silicon carbide, and graphite in carbonaceous chondrites: Implications for thermal processing in the solar nebula |doi=10.1016/j.gca.2003.07.019 |journal=Geochimica et Cosmochimica Acta |date=Dec 2003 |volume=67 |issue=24 |page=4823|bibcode=2003GeCoA..67.4823H }}{{cite journal |last1=Zinner |first1=E |last2=Amari |first2=S |last3=Guinness |first3=R |last4=Nguyen |first4=A |title=Presolar spinel grains from the Murray and Murchison carbonaceous chondrites |doi=10.1016/S0016-7037(03)00261-8 |journal=Geochimica et Cosmochimica Acta |date=Dec 2003 |volume=67 |issue=24 |page=5083|bibcode=2003GeCoA..67.5083Z }} These are crystals of material which survives from interstellar space, since before the formation of the Solar System. PSGs include silicon carbide ("Moissanite"){{cite journal |last1=Moissan |first1=H |title=Investigation of the Canon Diablo Meteorite |journal=Comptes Rendus de l'Académie des Sciences de Paris |date=1904 |volume=139 |page=773}} and micro-diamonds,{{cite journal |last1=Ksanda |first1=C |last2=Henderson |first2=E |title=Identification of diamond in the Canyon Diablo iron |journal=American Mineralogist |date=1939 |volume=24 |page=677}} as well as other refractory minerals such as corundum and zircon.{{cite journal |last1=Laspeyres |first1=H |last2=Kaiser |first2=E |title=Quartz and Zerkonkrystall im Meteoreisen Toluca von Mexico |journal=Zeitschrift für Krystallographie und Mineralogie |date=1895 |volume=24 |page=485}} The isotope levels of their elements do not match solar system levels, instead being closer to e. g., the interstellar medium. PSGs themselves may contain smaller PSGs.{{cite journal |last1=Bernatowicz |first1=T |last2=Amari |first2=S |last3=Zinner |first3=E |last4=Lewis |first4=R |title=Interstellar Grains within Interstellar Grains |journal=Astrophysical Journal Letters |date=Jun 1991 |volume=373 |page=L73 |doi=10.1086/186054|bibcode=1991ApJ...373L..73B }}

As with other meteorite classes, some carbon content is as carbides (often Cohenite, Fe₃C with e.g., nickel substitutions){{cite journal |last1=Brett |first1=R |title=Cohenite: its occurrence and a proposed origin |bibcode=1967GeCoA..31..143B |journal=Geochimica et Cosmochimica Acta |date=1967 |volume=31 |issue=2 |page=143|doi=10.1016/S0016-7037(67)80042-5 }} and carbonates such as calcite and dolomite.{{cite journal |last1=Nagy |first1=B |last2=Andersen |first2=C |title=Electron probe microanalysis of some carbonate, sulfate and phosphate minerals in the Orgueil meteorite |journal=American Mineralogist |date=1964 |volume=49 |page=1730}}{{cite conference |last1=Sofe |first1=M |last2=Lee |first2=M |last3=Lindgren |first3=P |last4=Smith |first4=C |title=CL Zoning of Calcite in CM Carbonaceous Chondrites and its Relationship to Degree of Aqueous Alteration |conference=74th Meteoritical Society Meeting |date=2011 |issue=5392}}{{cite journal |last1=de Leuw |first1=S |last2=Rubin |first2=A |last3=Wasson |first3=J |title=Carbonates in CM chondrites: Complex formational histories and comparison to carbonates in CI chondrites |doi=10.1111/j.1945-5100.2010.01037.x |journal=Meteoritics & Planetary Science |date=Jul 2010 |volume=45 |issue=4 |page=513|bibcode=2010M&PS...45..513D |s2cid=14208785 }} Aragonite appears, where CIs contain little or none.{{cite journal |last1=Lee |first1=M |last2=Lindgren |first2=P |last3=Sofe |first3=M |title=Aragonite, breunnerite, calcite and dolomite in the CM carbonaceous chondrites: High fidelity recorders of progressive parent body aqueous alteration |doi=10.1016/j.gca.2014.08.019 |journal=Geochimica et Cosmochimica Acta |date=Nov 2014 |volume=144 |page=126|bibcode=2014GeCoA.144..126L |doi-access=free }}

Total carbon compounds in CM chondrites are lower than in CI chondrites; however, more are aromatics.{{cite journal |last1=Cody |first1=G |last2=Alexander |first2=C |title=NMR studies of chemical structural variation of insoluble organic matter from different carbonaceous chondrite groups |doi=10.1016/j.gca.2004.08.031 |journal=Geochimica et Cosmochimica Acta |date=Feb 2005 |volume=69 |issue=4 |page=1085|bibcode=2005GeCoA..69.1085C }} Isotope profiling indicates these are meteoritic, not terrestrial.{{cite journal |last1=Cronin |first1=J Pizzarello S |last2=Frye |first2=J |title=13C NMR spectroscopy of the insoluble carbon of carbonaceous chondrites |bibcode=1982Metic..17..200C |journal=Geochimica et Cosmochimica Acta |date=Feb 1987 |volume=51 |issue=2 |pages=299–303 |doi=10.1016/0016-7037(87)90242-0 |pmid=11542083 }}

The organics of C-chondrites divide into soluble, and IOM (Insoluble Organic Matter). The soluble fraction would yield to the chemistry techniques of the mid-20th century,{{cite journal |last1=Easton |first1=A |last2=Lovering |first2=J |title=The analysis of chondritic meteorites |doi=10.1016/0016-7037(63)90040-1 |journal=Geochimica et Cosmochimica Acta |date=1963 |volume=27 |issue=7 |page=753|bibcode=1963GeCoA..27..753E }}{{cite journal |last1=Moss |first1=A |last2=Hey |first2=M |last3=Elliott |first3=C |last4=Easton |first4=A |title=Methods for the Chemical Analysis of Meteorites II: The major and some minor constituents of chondrites |doi=10.1180/minmag.1967.036.277.17 |journal=Mineralogical Magazine |date=Mar 1967 |volume=36 |issue=277 |page=101|bibcode=1967MinM...36..101M }} giving paraffin, naphthene and aromatics, with other contributions.{{cite journal |last1=Briggs |first1=M |last2=Mamikunian |first2=G |s2cid=10422212 |title=Organic Constituents of the Carbonaceous Chondrites |doi=10.1007/BF00212447 |journal=Space Science Reviews |date=May 1963 |volume=1 |issue=4 |pages=57–85 |pmid=11881656 |bibcode=1963SSRv....1..647B }}

The IOM is, however, the clear majority of the organic component; in 1963, Briggs and Mamikunian could only give it as "very high molecular weight". IOM itself divides into two components: thermally labile, and refractory.{{cite journal |last1=Remusat |first1=L |last2=Le Guillou |first2=C |last3=Rouzaud |first3=J |last4=Binet |first4=L |last5=Derenne |first5=S |last6=Robert |first6=F |title=Molecular study of insoluble organic matter in Kainsaz CO3 carbonaceous chondrite: Comparison with CI and CM IOM |doi=10.1111/j.1945-5100.2008.tb01115.x |journal=Meteoritics & Planetary Science |date=Jan 2007 |volume=43 |issue=7 |page=1099|s2cid=98683674 |doi-access= }}

Amino acids and other organics were first reported by multiple groups;{{cite journal |last1=Degens |first1=E |last2=Bajor |first2=M |s2cid=42359207 |title=Amino acids and sugars in the bruderheim and Murray meteorite |doi=10.1007/BF01178050 |journal=Die Naturwissenschaften |date=1963 |volume=49 |issue=24 |page=605}}{{cite journal |last1=Kaplan |first1=I |last2=Degens |first2=E |last3=Reuter |first3=J |title=Organic compounds in stony meteorites |doi=10.1016/0016-7037(63)90045-0 |journal=Geochimica et Cosmochimica Acta |date=Jul 1963 |volume=27 |issue=7 |page=805|bibcode=1963GeCoA..27..805K }} however, concentrations were low to undetectable,{{cite book |editor-last1=Kallman Bijl |editor-first1=H |title=Space Research |date=1960 |publisher=North-Holland Publishing Company |location=Amsterdam |page=1171 |chapter=Extraterrestrial Life: Some Organic Constituents of Meteorites}}{{cite journal |last1=Briggs |first1=M |s2cid=40559837 |title=Organic constituents of meteorites |doi=10.1038/1911137a0 |journal=Nature |date=1961 |volume=191 |issue=4794 |page=1137|bibcode=1961Natur.191.1137B }} and claimed to be terrestrial contamination.{{cite journal |last1=Hamilton |first1=P. B. |s2cid=4189815 |title=Amino acids on hands |doi=10.1038/205284b0 |pmid=14270714 |journal=Nature |date=1965 |volume=205 |issue=4968 |pages=284–5 |bibcode=1965Natur.205..284H }}{{cite journal |last1=Oró |first1=J |last2=Skewes |first2=H |s2cid=4275454 |title=Free Amino-Acids on Human Fingers: The Question of Contamination in Microanalysis |doi=10.1038/2071042a0 |pmid=5866306 |journal=Nature |date=1965 |volume=207 |issue=5001 |pages=1042–5 |bibcode=1965Natur.207.1042O }} The 1969 fall of the Murchison meteorite provided over 100 kg of sample, the largest CM ever. Specimens were recovered quickly, from a dry area. Combined with progress in, e.g., biochemistry and petrochemistry techniques, the question could be addressed more definitively: sugars{{cite journal |last1=Nuevo |first1=M |last2=Cooper |first2=G |last3=Sandford |first3=S |title=Deoxyribose and deoxysugar derivatives from photoprocessed astrophysical ice analogues and comparison to meteorites |doi=10.1038/s41467-018-07693-x |pmid=30563961 |pmc=6299135 |journal=Nature Communications |date=2018 |volume=9 |issue=1 |page=5276|bibcode=2018NatCo...9.5276N }} and amino acids{{cite journal |last1=Kvenvolden |first1=K |last2=Lawless |first2=J |last3=Pering |first3=K |last4=Peterson |first4=E |last5=Flores |first5=J |last6=Ponnamperuma |first6=C |s2cid=4147981 |title=Evidence for Extraterrestrial Amino-acids and Hydrocarbons in the Murchison Meteorite |doi=10.1038/228923a0 |pmid=5482102 |journal=Nature |date=Dec 1970 |volume=228 |issue=5275 |pages=923–6 |bibcode=1970Natur.228..923K }}{{cite journal |last1=Oró |first1=J |last2=Gibert |first2=J |last3=Lichtenstein |first3=H |last4=Wikstrom |first4=S |last5=Flory |first5=D |s2cid=4240808 |title=Amino-acids, Aliphatic and Aromatic Hydrocarbons in the Murchison Meteorite |doi=10.1038/230105a0 |pmid=4927006 |journal=Nature |date=Mar 1971 |volume=230 |issue=5289 |pages=105–6 |bibcode=1971Natur.230..105O }} existed in space, via meteorites. This includes non-terrestrial amino acids.{{cite journal |last1=Kvenvolden |first1=K |last2=Lawless |first2=J |last3=Pering |first3=K |s2cid=4147981 |title=Evidence for Extraterrestrial Amino-acids and Hydrocarbons in the Murchison Meteorite |journal=Nature |date=Dec 1970 |volume=228 |issue=5275 |pages=923–926 |doi=10.1038/228923a0|pmid=5482102 |bibcode=1970Natur.228..923K }}{{cite journal |last1=Koga |first1=T |first2=Naraoka |last2=H |title=A new family of extraterrestrial amino acids in the Murchison meteorite |doi=10.1038/s41598-017-00693-9 |pmid=28377577 |pmc=5428853 |journal=Scientific Reports |date=Apr 2017 |volume=7 |issue=1 |page=636|bibcode=2017NatSR...7..636K }} Multiple isotopes do not match Earth levels, strong evidence for non-contamination.{{cite book |last1=Mullie |first1=F Reisse J |title=Organic matter in carbonaceous chondrites, in Topics In Current Chemistry-Series 139 |date=1987 |publisher=Springer |location=New York |pages=83–117}}{{cite journal |last1=Engel |first1=M |last2=Macko |first2=S |s2cid=4411982 |title=Isotopic evidence for extraterrestrial non-racemic amino acids in the Murchison meteorite |doi=10.1038/38460 |pmid=9305838 |journal=Nature |date=Sep 1997 |volume=389 |issue=6648 |pages=265–8 |bibcode=1997Natur.389..265E }}{{cite journal |last1=Elsila |first1=J |last2=Charnley |first2=S |last3=Burton |first3=A |last4=Glavin |first4=D |last5=Dworkin |first5=J |title=Compound-specific carbon, nitrogen, and hydrogen isotopic ratios for amino acids in CM and CR chondrites and their use in evaluating potential formation pathways |doi=10.1111/j.1945-5100.2012.01415.x |journal= Meteoritics & Planetary Science|date=Sep 2012 |volume=47 |issue=9 |page=1517|bibcode=2012M&PS...47.1517E |hdl=2060/20120014482 |s2cid=19154600 |hdl-access=free }}

The levels of amino acids are higher in CMs than CIs.{{cite journal |last1=Botta |first1=O |last2=Martins |first2=Z |last3=Ehrenfreund |first3=P |title=Amino acids in Antarctic CM1 meteorites and their relationship to other carbonaceous chondrites |journal=Meteoritics & Planetary Science |date=Jan 2007 |volume=42 |issue=1 |pages=81–92 |doi=10.1111/j.1945-5100.2007.tb00219.x|bibcode=2007M&PS...42...81B |doi-access=free }}

Amino-like nitriles/cyanides{{cite journal |last1=Smith |first1=K |last2=House |first2=C |last3=Arevalo |first3=R |last4=Dworkin |first4=J |last5=Callahan |first5=M |title=Organometallic compounds as carriers of extraterrestrial cyanide in primitive meteorites |journal=Nature Communications |date=Jun 2019 |volume=10 |issue=1 |page=2777 |doi=10.1038/s41467-019-10866-x|pmid=31239434 |pmc=6592946 |bibcode=2019NatCo..10.2777S }} and heterocycles{{cite journal |last1=Stoks |first1=P |last2=Schwartz |first2=A |title=Nitrogen-heterocyclic compounds in meteorites: significance and mechanisms of formation |journal=Geochimica et Cosmochimica Acta |date=Apr 1981 |volume=45 |issue=4 |pages=563–69 |doi=10.1016/0016-7037(81)90189-7|bibcode=1981GeCoA..45..563S }} are also found. These related organics may be decomposition products or precursors.{{cite book |last1=Hayatsu |first1=R Anders E |title=Organic compounds in meteorites and their origins, in Topics in Current Chemistry 99 |date=1981 |publisher=Springer-Verlag |location=Berlin, Heidelberg |isbn=978-3-540-10920-4 |pages=1–37}}{{cite journal |last1=Schmitt-Kopplin |first1=P |last2=Gabelica |first2=Z |last3=Gougeon |first3=R |title=High molecular diversity of extraterrestrial organic matter in Murchison meteorite revealed 40 years after its fall |journal=PNAS |date=Feb 2010 |volume=107 |issue=7 |pages=2763–2768 |doi=10.1073/pnas.0912157107|pmid=20160129 |pmc=2840304 |bibcode=2010PNAS..107.2763S |doi-access=free }}{{cite journal |last1=Yamashita |first1=Y |last2=Naraoka |first2=H |title=Two homologous series of alkylpyridines in the Murchison meteorite |journal=Geochemical Journal |date=Jan 2014 |volume=48 |issue=6 |pages=519–525|doi=10.2343/geochemj.2.0340 |bibcode=2014GeocJ..48..519Y |doi-access=free }}

The early analyses did not record optical rotation, and gave meteoritic organics as racemic.{{cite journal |last1=Mueller |first1=G |title=The properties and theory of genesis of the carbonaceous complex within the cold bokevelt meteorite |doi=10.1016/0016-7037(53)90061-1 |journal=Geochimica et Cosmochimica Acta |date=Aug 1953 |volume=4 |issue=1–2 |page=1|bibcode=1953GeCoA...4....1M }} As amino acids are diverse but low, the discovery of meteoritic chirality had to await the separation of IOM.{{cite journal |last1=Engel |first1=M Nagy, B |s2cid=4341990 |title=Distribution and enantiomeric composition of amino acids in the Murchison meteorite |doi=10.1038/296837a0 |journal=Nature |date=Apr 1982 |volume=296 |issue=5860 |page=837|bibcode=1982Natur.296..837E }} Handedness of some meteorite organics is now accepted (see below), including in the soluble organic fraction.{{cite journal |last1=Pizzarello |first1=S |last2=Yarnes |first2=C |title=Chiral molecules in space and their possible passage to planetary bodies recorded by meteorites |doi=10.1016/j.epsl.2018.05.026 |journal=Earth and Planetary Science Letters |date=Aug 2018 |volume=496 |page=198|bibcode=2018E&PSL.496..198P |s2cid=102863818 }}{{cite journal |last1=Pizzarello |first1=S |last2=Yarnes |first2=C |title=The soluble organic compounds of the Mukundpura meteorite: A new CM chondrite fall |doi=10.1016/j.pss.2018.07.002 |journal=Planetary and Space Science |date=Dec 2018 |volume=164 |page=127|bibcode=2018P&SS..164..127P |s2cid=125844045 }}

1. Kvenvolden et al. 1970; 2. Meierheinrich{{cite journal |last1=Meierhenrich |first1=U |last2=Muñoz Caro |first2=G |last3=Bredehöft |first3=J |last4=Jessberger |first4=E |last5=Thiemann |first5=W |title=Identification of diamino acids in the Murchison meteorite |journal=PNAS |date=22 Jun 2004 |volume=101 |issue=25 |pages=9182–86 |doi=10.1073/pnas.0403043101|pmid=15194825 |pmc=438950 |bibcode=2004PNAS..101.9182M |doi-access=free }} et al. 2004 3. Martins et al. 2015{{cite journal |last1=Martins |first1=Z |last2=Modica |first2=P |last3=Zanda |first3=B |last4=Le Sergeant d'Hendecourt |first4=L |title=The amino acid and hydrocarbon contents of the Paris meteorite: Insights into the most primitive CM chondrite |journal=Meteoritics & Planetary Science |date=May 2015 |volume=50 |issue=5 |pages=926–43 |doi=10.1111/maps.12442|bibcode=2015M&PS...50..926M |hdl=10044/1/25091 |s2cid=95549163 |hdl-access=free }} 4. Koga et al. 2017; 5. Rudraswami et al. 2018;{{cite journal |last1=Rudraswami |first1=N |last2=Naik |first2=A |last3=Tripathi |first3=R |last4=Bhandari |first4=N |last5=Karapurkar |first5=S |last6=Prasad |first6=M |last7=Babu |first7=E |last8=Sarathi |first8=V |title=Chemical, isotopic and amino acid composition of Mukundpura CM2.0 (CM1) chondrite: Evidence of parent body aqueous alteration |journal=Geoscience Frontiers |date=Feb 2018 |volume=10 |issue=2 |pages=495–504 |doi=10.1016/j.gsf.2018.02.001|doi-access=free }} 6. Pizzarello, Yarnes 2018

The first publication of anomalous gas in a carbonaceous chondrite (Murray) was in 1960.{{cite journal |last1=Reynolds |first1=J |title=Isotopic Composition of Primordial Xenon |journal=Phys. Rev. Lett. |date=Apr 1960 |volume=4 |issue=7 |pages=351–354 |doi=10.1103/PhysRevLett.4.351|bibcode=1960PhRvL...4..351R }} "Gas-rich meteorites" of other classes host their gas in dark liths,{{cite journal |last1=Heymann |first1=D |last2=Mazor |first2=E |title=Light-Dark Structure and Rare Gas Content of the Carbonaceous Chondrite Nogoya |journal=Journal of Geophysical Research: Atmospheres |date=May 1967 |volume=72 |issue=10 |pages=2704–2707 |doi=10.1029/JZ072i010p02704|bibcode=1967JGR....72.2704H }} in most cases closely related to CM.{{cite book |last1=Wasson |first1=J |title=Meteorites: Their record of early solar-system history |date=1985 |publisher=W. H. Freeman and Co. |location=New York |isbn=978-0716717003 |page=59}}

Gases in meteorites include primordial, solar (both solar wind, and a distinct solar flare component), radiogenic (due to cosmic-ray exposure), and fissile (decay products).{{cite journal |last1=Goswami |first1=J |last2=Lal |first2=D |last3=Wilkening |first3=L |s2cid=121335431 |title=Title: Gas-rich meteorites – Probes for particle environment and dynamical processes in the inner solar system |journal=Space Science Reviews |date=Jan–Feb 1984 |volume=37 |pages=111–159 |doi=10.1007/BF00213959}} Host materials are generally carbonaceous,{{cite journal |last1=Lewis |first1=R |last2=Srinivasan |first2=B |last3=Anders |first3=E |title=Host Phase of a Strange Xenon Component in Allende |journal=Science |date=26 Dec 1975 |volume=490 |issue=4221 |pages=1251–1262 |doi=10.1126/science.190.4221.1251|bibcode=1975Sci...190.1251L |s2cid=94192045 }} including presolar grains: diamond,{{cite journal |last1=Huss |first1=G |last2=Lewis |first2=R |title=Noble gases in presolar diamonds I: Three distinct components and their implications for diamond origins |journal=Meteoritics |date=1994 |volume=29 |issue=6 |page=791|doi=10.1111/j.1945-5100.1994.tb01094.x |bibcode=1994Metic..29..791H |doi-access=free }} silicon carbide,{{cite journal |last1=Bernatowicz |first1=T |last2=Fraundorf |first2=G |last3=Ming |first3=T |last4=Anders |first4=E |last5=Wopenka |first5=B |last6=Zinner |first6=E |last7=Fraundorf |first7=P |s2cid=4361807 |title=Evidence for interstellar silicon carbide in the Murray carbonaceous meteorite |journal=Nature |date=1987 |volume=330 |pages=728–730|doi=10.1038/330728a0 }}{{cite journal |last1=Zinner |first1=E |last2=Ming |first2=T |last3=Anders |first3=E |s2cid=4306270 |title=Large isotopic anomalies of silicon, carbon, nitrogen, and noble gases in interstellar silicon carbode in the Murray carbonaceous meteorite |journal=Nature |date=1987 |volume=330 |page=730|doi=10.1038/330730a0 }} graphite,{{cite journal |last1=Amari |first1=S |last2=Anders |first2=E |last3=Virag |first3=A |last4=Zinner |first4=E |s2cid=10272604 |title=Interstellar graphite in meteorites |journal=Nature |date=1990 |volume=345 |issue=6272 |page=238|doi=10.1038/345238a0 |bibcode=1990Natur.345..238A }} and organics.

Nogoya is one particularly gas-rich CM chondrite.{{cite journal |last1=Black |first1=D |title=On the origins of trapped helium, neon and argon isotopic variations in meteorites—II. Carbonaceous meteorites |journal=Geochimica et Cosmochimica Acta |date=Mar 1972 |volume=36 |issue=3 |pages=377–394 |doi=10.1016/0016-7037(72)90029-4|bibcode=1972GeCoA..36..377B }}

Micrometeorites lose significant amounts of their gas to entry heating,{{cite journal |last1=Füri |first1=E |last2=Aléon-Toppani |first2=A |last3=Marty |first3=B |last4=Libourel |first4=G |last5=Zimmermann |first5=L |title=Effects of atmospheric entry heating on the noble gas and nitrogen content of micrometeorites |journal=Earth and Planetary Science Letters |date=Sep 2013 |volume=377 |pages=1–12 |doi=10.1016/j.epsl.2013.07.031|bibcode=2013E&PSL.377....1F }} but still deliver quantifiable amounts.{{cite conference |last1=Nakamura |first1=T |last2=Noguchi |first2=T |last3=Ozono |first3=Y |last4=Osawa |first4=T |last5=Nagao |first5=K |title=Mineralogy of Ultracarbonaceous Large Micrometeorites |conference=68th Meteoritical Society |date=12 Sep 2005 |issue=5046}}

Isotope studies have become vital in examining natural histories.{{cite journal |last1=Clayton |first1=R |last2=Onuma |first2=N |last3=Grossman |first3=L |last4=Mayeda |first4=T |title=Distribution of the pre-solar component in Allende and other carbonaceous chondrites |doi=10.1016/0012-821X(77)90005-X |journal=Earth and Planetary Science Letters |date=Mar 1977 |volume=32 |issue=2 |page=209|bibcode=1977E&PSL..34..209C }} Oxygen, in particular, forms quite stable oxides; it requires significant events, processes, or energies to segregate isotopes by their slight mass differences.

CM and CI chondrites have a measurable difference in oxygen isotope levels. This suggests a different formation temperature, and hence a different zone of the young Solar System. However, CM and CO meteorites were found to have similar oxygen isotopes, indicating a relationship.{{cite journal |last1=Clayton |first1=R |last2=Mayeda |first2=T |title=Oxygen isotope studies of carbonaceous chondrites |doi=10.1016/S0016-7037(99)00090-3 |journal=Geochimica et Cosmochimica Acta |date=Jul 1999 |volume=63 |issue=13–14 |page=2089|bibcode=1999GeCoA..63.2089C }}{{cite conference |last1=Greenwood |first1=R |last2=Howard |first2=K |last3=Franchi |first3=I |last4=Zolensky |first4=M |last5=Buchanan |first5=P |last6=Gibson |first6=J |title=Oxygen Isotope Evidence For The Relationship Between CM And CO Chondrites: Could They Both Coexist On A Single Asteroid? |conference=45th LPSC |date=Mar 2014 |issue=2610}}

CMs, like other C-chondrites, are subjected to a serious observation bias. C-chondrites are friable, due to both macro-scale porosity and micro-scale matrices of phyllosilicates, with many chondrules also having layers such as phyllosilicates.{{cite journal |last1=Hanna |first1=R |last2=Ketcham |first2=R |last3=Zolensky |first3=M |last4=Behr |first4=W | doi=10.1016/j.gca.2015.09.005 |title=Impact-induced brittle deformation, porosity loss, and aqueous alteration in the Murchison CM chondrite |journal=Geochimica et Cosmochimica Acta |date=Dec 2015 |volume=171 |page=256|bibcode=2015GeCoA.171..256H |doi-access=free }} The meteorites have been described as "tuff" (compacted volcanic ash).{{cite journal |last1=Merrill |first1=G |title=On metamorphism in meteorites |doi=10.1130/GSAB-32-395 |journal=Bull. Geol. Soc. Am. |date=1921 |volume=32 |issue=4 |page=395|bibcode=1921GSAB...32..395M }}

As one example, the Tagish Lake meteorite provided ~10 kg of samples, from a meteor estimated to be 60–90 tons before entry.{{cite journal |last1=Hildebrand |first1=A |last2=McCausland |first2=P |last3=Brown |first3=P |last4=Longstaffe |first4=F |last5=Russell |first5=S |last6=Tagliaferri |first6=E |title=The fall and recovery of the Tagish Lake meteorite |bibcode=2006M&PS...41..407H |journal=Meteoritics & Planetary Science |date=2006 |volume=41 |issue=3 |page=407|doi=10.1111/j.1945-5100.2006.tb00471.x |doi-access=free }}

By contrast, many ordinary chondrite meteorites are tougher{{cite journal |last1=Flynn |first1=G |last2=Consolmagno |first2=G |last3=Brown |first3=P |last4=Macke |first4=R |title=Physical properties of the stone meteorites: Implications for the properties of their parent bodies |doi=10.1016/j.chemer.2017.04.002 |journal=Geochemistry |date=Sep 2018 |volume=78 |issue=3 |page=269|bibcode=2018ChEG...78..269F |doi-access=free }} and overrepresented,{{cite journal |last1=Heck |first1=P |last2=Schmitz |first2=B |last3=Bottke |first3=W |last4=Rout |first4=S |last5=Kita |first5=N |title=Rare meteorites common in the Ordovician period |journal=Nature Astronomy |date=Jan 2017 |volume=1 |issue=2 |pages=0035 |doi=10.1038/s41550-016-0035|bibcode=2017NatAs...1E..35H |s2cid=102488048 }} and iron meteorites even more so.{{cite book |last1=Grady |first1=M |last2=Hutchison |first2=R |title=Meteorites: Flux with Time and Impact Effects |publisher=Geological Society of London |date=1998 |isbn=9781862390171 |pages=67–70}} sec. The frequency of meteorite types

CI and CM chondrites in particular are then subject to weathering on the ground. As large fractions of C-chondrite material are water soluble, ordinary chondrites and irons are more likely to be recognized and recovered. Greater coverage of hot deserts and Antarctica has resulted in many C-chondrite specimens.{{cite journal |last1=Cassidy |first1=W |last2=Rancitelli |first2=L |title=Antarctic Meteorites: The abundant material being discovered in Antarctica may shed light on the evolution of meteorite parent bodies and the history of the solar system |jstor=27851347 |journal=American Scientist |date=Mar 1982 |volume=70 |issue=2 |pages=156–164 }}{{cite book |editor-last1=Lauretta |editor-first1=D |editor-last2=McSween |editor-first2=H |title=Meteorites and the Early Solar System II |date=2006 |publisher=University of Arizona Press |location=Tucson |isbn=9780816525621 |page=853}} Ch. Weathering of Chondritic Meteorites, Bland, P., Zolensky, M., Benedix, G., Sephton, M.{{cite web |last1=Korotev |first1=Randy L. |title=Some Meteorite Statistics |url=http://meteorites.wustl.edu/meteorite_types.htm |website=Department of Earth and Planetary Sciences, Washington University in St. Louis |publisher=Washington University in St. Louis |accessdate=14 Sep 2019}}

{{Main|Parent body}}

As carbonaceous specimens, CM and other groups are widely assumed to be from carbonaceous asteroids. This includes the explicit C-type asteroids, and to various degrees the related G-, B- (including the deprecated F-), D-, and P-types.{{cite book |title=Encyclopedia of Planetary Science. Encyclopedia of Earth Science Series |date=1997 |publisher=Springer |location=Dordrecht |isbn=978-0-412-06951-2 |page=486}} Chapter: Meteorite parent bodies, Britt, D., Lebofsky, L.{{cite journal |last1=Cloutis |first1=E |last2=Binzel |first2=R |last3=Gaffey |first3=M |title=Establishing Asteroid–Meteorite Links |doi=10.2113/gselements.10.1.25 |journal=Elements |date=Feb 2014 |volume=10 |page=25}}{{cite journal |last1=Lee |first1=M Cohen B King A Greenwood R |title=The diversity of CM carbonaceous chondrite parent bodies explored using Lewis Cliff 85311 |doi=10.1016/j.gca.2019.07.027 |journal=Geochimica et Cosmochimica Acta |date=Jul 2019 |volume=257|pages=224–244 |bibcode=2019GeCoA.264..224L |url=http://eprints.gla.ac.uk/190417/1/190417.pdf |doi-access=free }} As carbonaceous types are the majority of asteroids,{{cite web |title=Asteroids (from the NEAR press kit) |url=https://nssdc.gsfc.nasa.gov/planetary/text/asteroids.txt |publisher=NSSDC |accessdate=27 Oct 2019}}{{cite book |editor-last1=Orgel |editor-first1=L |title=Evaluating the Biological Potential in Samples Returned from Planetary Satellites and Small Solar System Bodies: Framework for Decision Making |date=1998 |publisher=National Academy of Sciences National Academy Press |location=Washington DC |isbn=978-0-309-06136-0 |chapter=4 Asteroids and Meteorites

}} "it is likely that the C-type asteroids (which are overwhelmingly the most abundant type in the main belt, especially the middle and outer parts) are represented in various meteorite collections by carbonaceous chondrites"{{cite web |title=Asteroids: Structure and composition of asteroids |url=https://www.esa.int/Science_Exploration/Space_Science/Asteroids_Structure_and_composition_of_asteroids |website=ESA – Science & Exploration |publisher=European Space Agency |accessdate=27 Oct 2019}} but only a few percent of recovered meteorites, selection/filtering effects must be severe.

Aside from the diversity of CMs, and the diversity of C-asteroid types and subtypes (besides the asteroids themselves), the question of parentage is very open as of this writing. The Almahata Sitta meteorite was catalogued as a ureilite, an entirely different meteorite class. However, it entered as asteroid 2008 TC₃. A crude spectrum was taken before entry, which would have placed 2008 TC₃ as a F- or B-type.{{cite journal |last1=Burbine |first1=T |title=Advances in determining asteroid chemistries and mineralogies |doi=10.1016/j.chemer.2015.09.003 |journal=Chemie der Erde |date=2016 |volume=76 |issue=2 |page=181|bibcode=2016ChEG...76..181B |doi-access=free }}

Some amount of space weathering is seen to occur on carbonaceous asteroids; this complicates attempts to link parents via spectroscopy.{{cite journal |last1=Lantz |first1=C |last2=Clark |first2=B |last3=Barucci |first3=M |last4=Lauretta |first4=D |title=Evidence for the effects of space weathering spectral signatures on low albedo asteroids |doi=10.1051/0004-6361/201321593 |journal=Astronomy and Astrophysics |date=May 2013 |volume=554 |page=A138|bibcode=2013A&A...554A.138L |doi-access=free }}{{cite journal |last1=Matsuoka |first1=M |last2=Nakamura |first2=T |last3=Kimura |first3=Y |last4=Hiroi |first4=T |last5=Nakamura |first5=R |last6=Okumura |first6=S |last7=Sasaki |first7=S |title=Pulse-laser irradiation experiments of Murchison CM2 chondrite for reproducing space weathering on C-type asteroids |doi=10.1016/j.icarus.2015.02.029 |journal=Icarus |date=Mar 2015 |volume=254 |page=135|bibcode=2015Icar..254..135M }}{{cite journal |last1=Thompson |first1=M |last2=Loeffler |first2=M |last3=Morris |first3=R |last4=Keller |first4=L |last5=Christoffersen |first5=R |doi=10.1016/j.icarus.2018.09.022 |title=Spectral and chemical effects of simulated space weathering of the Murchison CM2 carbonaceous chondrite |journal=Icarus |date=Feb 2019 |volume=319 |page=499|bibcode=2019Icar..319..499T |doi-access=free }}

A hypothesis persists that all CMs stem from a single parent.{{cite journal |last1=Bland |first1=P |last2=Alard |first2=O |last3=Benedix |first3=G |last4=Kearsley |first4=A |title=Volatile fractionation in the early solar system and chondrule/matrix complementarity |doi=10.1073/pnas.0501885102 |pmid=16174733 |pmc=1224360 |journal=PNAS |date=Sep 2005 |volume=102 |issue=39 |pages=13755–60 |bibcode=2005PNAS..10213755B |doi-access=free }}{{cite conference|last1=Franchi |first1=I |last2=Greenwood |first2=R |last3=Howard |first3=K |last4=King |first4=A |last5=Lee |first5=M |last6=Anand |first6=M |last7=Findlay |first7=R |title=Oxygen Isotope Variation Of CM And Related Chondrites: Multiple Parent Bodies Or A Single Heterogeneous Source? |conference=Meteoritical Society Meeting, 2019 |date=2019 |page=6482}}

Brecciated meteorites include monomict breccias (re-formed from rock fragments on a single type) and polymict ones (incorporating different source rocks). Polymict meteorites record exchanges between sites. C-chondrite materials are often found in such meteorites.{{cite journal |last1=Mueller |first1=G |s2cid=4223453 |title=Significance of Inclusions in Carbonaceous Meteorites |journal=Nature |date=Apr 1966 |volume=210 |issue=5032 |pages=151–155 |doi=10.1038/210151a0|bibcode=1966Natur.210..151M |doi-access=free }}{{cite journal |last1=Zolensky |first1=M |last2=Weisberg |first2=M |last3=Buchanan |first3=P |last4=Mittlefehldt |first4=D |title=Mineralogy of carbonaceous chondrite clasts in HED achondrites and the Moon |journal=Meteoritics & Planetary Science |date=Jul 1996 |volume=31 |issue=4 |pages=518–37 |doi=10.1111/j.1945-5100.1996.tb02093.x|bibcode=1996M&PS...31..518Z }}

• PRA 04401 – nominally a HED, contains as much CM or CM-like material in clasts as HED material{{cite journal |last1=Herrin |first1=J |last2=Zolensky |first2=M |last3=Cartwright |first3=J |last4=Mittlefehldt |first4=D |last5=Ross |first5=D |title=Carbonaceous Chondrite-Rich Howardites; The Potential For Hydrous Lithologies On The HED Parent |journal=Lunar and Planetary Science Conference |bibcode=2011LPI....42.2806H |location=42nd LPSC |date=Mar 2011 |issue=1608|pages=2806 }}
• Kaidun – a "kitchen sink"{{cite web |last1=Martel |first1=L V |title=Kaidun – A Meteorite with Everything but the Kitchen Sink |url=http://www.psrd.hawaii.edu/Oct09/Kaidun_meteorite.html |website=Planetary Science Research Discoveries |accessdate=6 Oct 2019}} breccia
• Supuhee
• Plainview
• Jodzie

• Formation and history
• Origin of Earth's water
• Origin of life

• Mighei – 1889; from which the group name derives
• Cold Bokkevelt – 1838; a find, but from an arid region, and considered reasonably unaltered
• Nogoya – 1879;
• Boriskino – 1930;
• Murray – 1950;
• Murchison – 1969; large total known weight of 100 kg recovered, resulting in extensive study
• Yamato 74662 – 1974; first Antarctic CM

{{Expand list|date=September 2019}}

• Aguas Zarcas – Apr 2019 fall, specimens recovered quickly; >20 kg
• Winchcombe meteorite
• Mukundpura meteorite – 6 June 2017 fall, broke up during impact; 2.2 kg of fragments were recovered within hours

• Evaporite and Mudstone
• Oil shale
• Tholin and Kerogen
• List of interstellar and circumstellar molecules

• Mason, B. The Carbonaceous Chondrites. 1962 Space Sciences Reviews vol. 1, p. 621
• Meteorites and the Early Solar System, Kerridge, J. Matthews, M. eds. 1988 University of Arizona Press, Tucson {{ISBN|9780816510634}}
• Planetary Materials, Papike, J., ed. 1999 Mineralogical Society of America, Washington DC {{ISBN|0-939950-46-4}}
• The Catalogue of Meteorites, Grady, M. ed. 2000 Cambridge University Press, Cambridge {{ISBN|0 521 66303 2}}
• Meteorites and the Early Solar System II, Lauretta, D. McSween, H. eds. 2006 University of Arizona Press, Tucson {{ISBN|9780816525621}}

{{reflist}}

{{Meteorites}}

clan

Category:Meteorite groups