Lunar Meteorite: Allan Hills A81005

Allan Hills, Transantarctic Mountains, Antarctica

The meteorite has a partial greenish fusion crust. It is somewhat vesicular, which is characteristic of fusion crusts on lunar regolith breccias. Regolith at the lunar surface contains implanted atoms of solar wind, mostly hydrogen and helium. This gas is released when the exterior of the stone melts as it passes through Earth’s atmosphere. Image credit: NASA/JSC S82-35869 (color adjusted)

Many clasts are visible on this broken face.  Like other lunar regolith breccias, but unlike many terrestrial sedimentary rocks, the clasts are unsorted – they come in a complete range of sizes. Image credit: NASA/JSC S82-35865 (color adjusted)

Another view of the meteorite. Image credit: NASA.JSC S83-34612

Lunar regolith breccias are fractal objects – regardless of the scale, they look similar.  This image is a photomicrograph of a thin section of a fragment of ALHA 81005.  The width of the fragment is ~3 mm, a factor-of-10 less than the width of broken face of the whole meteorite. Photo credit: Randy Korotev

Listed in The Meteoritical Bulletin, No. 76, Meteoritics 29, 100-143 (1994)

From Antarctic Meteorite Newsletter, Vol. 6, No. 1, February (1983)

Allan Hills A81005 or ALHA 81005 (abbreviations: ALHA81005 and ALH 81005)

Antarctica
Found: 1982 January 18
Mass: 31.4 g (1 piece)

Classification: Anorthositic Breccia

Physical Description: Roberta Score. This is an unusual looking sample! Flow marks are apparent on the exterior which is covered with a pitted, glassy, greenish-tan colored crust. Immediately underneath this crust, the surface is a “dusty” gray color. The interior consists of abundant angular clasts, which range in color from gray to white, set in a black matrix. The size of the clasts are as small as submillimeter and as large as 8 mm in diameter. The sample is very coherent. Some areas of oxidation were noted. Dimensions: 3 x 2.5 x 3 cm.

Petrographic Description: Brian Mason. The specimen is a microbreccia of clasts (maximum dimension 4 mm) in a translucent to semi-opaque dark brown glassy matrix showing flow structure in places; clast:matrix ratio is approximately 40:60. The larger clasts are polymineralic, the smaller (less than 0.3 mm) may be individual mineral grains. The clasts consist largely of plagioclase, together with some pyroxene and occasional olivine; most of the mineral grains are plagioclase. The clasts show a variety of textures, including gabbroic, diabasic, and basaltic; many have been shocked and partly granulated. Some of the clasts resemble eucrites, but many appear to be more feldspathic than most eucrites. The section is notable for the complete absence of opaque minerals, except for a 1 mm metal grain. Microprobe analyses show that the plagioclase is very Ca-rich, averaging An97 (range An95-98); pyroxene is variable in composition, Wo1-41, En44-79, Fs7-47 (richer in En than most eucrite pyroxenes); several grains of olivine, Fa11-40, were analyzed. The meteorite is a breccia, but more feldspathic than most eucrites; some of the clasts resemble the anorthositic clasts described from lunar rocks.

Randy Says…

Allan Hills A81005 is the first meteorite to be recognized as originating from the Moon. It was suspected to be lunar in the field and when first examined in the lab (above). After many studies (below) it was proven to be of lunar origin in the spring of 1983, a little over 10 years after the last Apollo mission to the Moon.

More Information

Meteoritical Bulletin Database

Allan Hills A81005

Lunar Meteorite Compendium

Allan Hills A81005

Map

ANSMET Location Map

References

Bogard D. D. (1983) A meteorite from the MoonGeophysical Research Letters 10, 773.

Bogard D. D. and Johnson P. (1983) Trapped solar gases in the ALHA81005 lunar(?) meteorite.  Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 1-2, abstract #6001.

Bogard D. D. and Johnson P. (1983) Trapped noble gases indicate lunar origin for Antarctic meteoriteGeophysical Research Letters 10, 801-803.

Boynton W. V. and Hill D. H. (1983) Minor and trace elements in clast and whole rock samples of Allan Hills A81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 3-4, abstract #6002.

Boynton W. V. and Hill D. H. (1983) Composition of bulk fragments and a possible pristine clast from Allan Hills A81005Geophysical Research Letters 10, 837-840.

Brum J. T., McLeod C. L., Gawronska A., Shaulis B., Duley M., Edelmann R., and M. Loocke (2019) Early lunar chronology: insights from Allan Hills (ALHA) 81005 meteorite (abstract). 50th Lunar and Planetary Science Conference, abstract no. 2012.

Brum J. T., McLeod C. L., Shaulis B., Duley M., and Loocke M. (2020) Investigating the history of Allan Hills (ALHA) 81005: What a meteorite’s components can tell us about it’s past. 51st Lunar and Planetary Science Conference, abstract no. 2919.

Calzada-Diaz A., Joy K. H., Crawford I. A., and Nordheim T. A. (2015) Constraining the source regions of lunar meteorites using orbital geochemical dataMeteoritics & Planetary Science 50, 214-228.

Chen J. H. and Wasserburg G. J. (1985) U-Th isotopic studies on meteorite ALHA81005 and Ibitira14th Lunar and Planetary Science Conference, 119–120.

Delano J. W. (1990) Constraints on the highlands source-area of lunar meteorite ALHA 81005 using chemical compositions of glassesLunar and Planetary Science XXI, 276-277.

Delano J. W. (1991) Geochemical comparison of impact glasses from lunar meteorites ALHA81005 and MAC88105 and Apollo 16 regolith 64001Geochimica et Cosmochimica Acta 55, 3019-3029.

Desnoyers C. and Michel-Lévy M. C.(1983) The olivine in the lunar meteorite ALHA 81005Meteoritics 18, 290.

Eugster O. (1989) History of meteorites from the Moon collected in AntarcticaScience 245, 1197-1202.

Evans J. C. and Reeves (1983) Aluminum-26 content of ALHA 81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 6-7, abstract #6004.

Fritz J. (2012) Impact ejection of lunar meteorites and the age of Giordano BrunoIcarus 221, 1183-1186.

Goodrich C.A., Taylor G. J., Keil K., Boynton W. V., and Hill D. H. (1984) Petrology and chemistry of hyperferroan anorthosites and other clasts from lunar meteorite ALHA81005Proceedings of the 15th Lunar and Planetary Science Conference, in Journal of Geophysical Research 89, C87-C94.

Goodrich C.A., Taylor G. J., Keil K., (1985) An apatite-rich, ferroan, mafic lithology from lunar meteorite ALHA81005Proceedings of the 16th Lunar and Planetary Science Conference, in Journal of Geophysical Research 90, C405-C414.

Gorman J. and Gross J. (2012) Spinel-rich lithologies on the Moon: An experimental study of possible precursor melt compositions43rd Lunar and Planetary Science Conference, abstract no. 1125.

Grady M. M. and Pillinger C. T. (1990) The carbon and nitrogen stable isotope geochemistry of two lunar meteorites: ALHA-81005 and Y-86032Proceedings of the NIPR Symposium on Antarctic Meteorites 3, 27-39.

Gross J. (2014) Can chondritic clasts in lunar meteorite Allan Hills A81005 constrain early Solar System processes? Evidence from oscillatory zoning in olivine. 77th Annual Meeting of the Meteoritical Society, abstract no. 5381.

Gross J. and Treiman A. H. (2010) New insights into the complex history of lunar highlands: ALHA 81005 under reinvestigation41st Lunar and Planetary Science Conference, abstract no. 2180.

Gross J. and Treiman A. H. (2010) Dispersed Fe/Mn ratios of lunar rocks: ALHA81005’s view from the farside. Geochimica et Cosmochimica Acta 74, Supplement 1, A356.

Gross J. and Treiman A. H. (2010) Massif anorthosites in ALHA 81005: Possible origin from a diapir?. 73rd Annual Meeting of the Meteoritical Society, abstract no. 5435.

Gross J., and Treiman A. H. (2011) Unique spinel-rich lithology in lunar meteorite ALHA 81005: Origin and possible connection to M3 observations of the farside highlandsJournal of Geophysical Research 116, E10009. doi:10.1029/2011JE003858.

Gross J., Treiman A. H., and Filiberto J. (2011) Constraints on the geochemical variations and evolution of the lunar crust and mantle as revealed by Fe, Mn, Cr concentrations in olivine42nd Lunar and Planetary Science Conference, abstract no. 2805.

Gross J., Treiman A. H., and Mercer C. M. (2012) Sinking the lunar magma ocean: New evidence from meteorites and the return of serial magmatism43rd Lunar and Planetary Science Conference, abstract no. 2306.

Gross J., Treiman A. H., and Mercer C. (2012) Lunar feldspathic meteorites: constraints on the geology of the lunar farside highlands, and the origin of the lunar crustSecond Conference on the Lunar Highlands Crust, abstract no. 9003.

Gross J., Isaacson P., Filiberto F., and Treiman A. H. (2013) Spinel-rich lithologies on the moon: linking samples, experiments, and remote sensing76th Annual Meeting of the Meteoritical Society, abstract no. 5114.

Gross J., Treiman A. H., and Mercer C. M. (2014) Lunar feldspathic meteorites: Constraints on the geology of the lunar highlands, and the origin of the lunar crustEarth & Planetary Science Letters 388, 318-328.

Isaacson P. J., Liu Y., Patchen A., Pieters C. M., and Taylor L. A. (2009) Integrated analyses of lunar meteorites: Expanded data for lunar ground truth40th Lunar and Planetary Science Conference, abstract no. 2119.

Isaacson P. J., Liu Y., Patchen A. D., Pieters C. M., and Taylor L. A. (2010) Spectroscopy of lunar meteorites as constraints for ground truth: Expanded sample collection diversity41st Lunar and Planetary Science Conference, abstract no. 1927.

Isaacson P. J., Hiroi T., Hawke B. R., Lucey P. G., Pieters C. M., Liu Y., Patchen A., and Taylor L. A. (2013) Lunar meteorite geo-logic context: New constraints from VNIR spectroscopy and geochemistry44th Lunar and Planetary Science Conference, abstract no. 1134.

Joy K. H., Nagashima K., Huss G. R., Zolensky M. E., and Kring D. A. (2012) Mineral chemistry and oxygen isotope analysis of a chondritic projectile in lunar meteorite Pecora Escarpment 0200743rd Lunar and Planetary Science Conference, abstract no. 1021.

Jull A. J. T. and Donahue, D. J. (1992) 14C Terrestrial ages of two lunar meteorites, ALHA 81005 and EET 87521Lunar and Planetary Science XXIII, 637-638.

Kallemeyn G. W. (1983) ALHA81005: A new sample from the lunar highlands?,  Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 10-11, abstract #6006.

Kallemeyn G. W. and Warren P. H. (1983) Compositional implications regarding the lunar origin of the ALHA81005 meteoriteGeophysical Research Letters 10, 833-836.

Korotev R. L. (2005) Lunar geochemistry as told by lunar meteoritesChemie der Erde 65, 297-346.

Korotev R. L. and Zeigler R. A. (2014) Chapter 6. ANSMET Meteorites from the Moon, Thirty-five Seasons of U.S. Antarctic Meteorites (1976–2010): A Pictorial Guide to the Collection (editors K. Righter, R. P. Harvey, C. M. Corrigan, and T. J. McCoy), 101–130, Special Publications 68, American Geophysical Union, Washington, D. C., 296 pages, ISBN: 978-1-118-79832-4.

Korotev R. L., Haskin L. A., and Lindstrom M. M. (1983) Lunar highlands breccia 81005 (ALHA): So Apollo 18 flew, but where did it sample? Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 12-13, abstract #6007.

Korotev R. L., Lindstrom M. M., Lindstrom D. J., and Haskin L. A. (1983) Antarctic meteorite ALHA81005 – Not just another lunar anorthositic noriteGeophysical Research Letters 10, 829-832.

Korotev R. L., Jolliff B. L., Zeigler R. A., and Haskin L. A. (2003) Compositional constraints on the launch pairing of three brecciated lunar meteorites of basaltic compositionAntarctic Meteorite Research 16, 152-175.

Kurat G. and Brandstätter F. (1983) Meteorite ALHA 81005: A lunar highland breccia. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 14-15, abstract #6008.

Kurat G. and Brandstätter F. (1983) Meteorite ALHA81005: Petrology of a new lunar highland sampleGeophysical Research Letters 10, 795-798.

Laul J. C., Smith M. R., and Schmitt R. A. (1983) ALHA 81005 meteorite: Chemical evidence for lunar Highland origin. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 16-17, abstract #6009.

Maloy A. K., Treiman A. H., and Shearer C. K. Jr. (2004) A ferroan gabbronorite clast in lunar meteorite ALHA81005: Major and trace element composition, and originLunar and Planetary Science XXXV, abstract no. 1159.

Maloy A. K., Treiman A. H., Shearer C. K. Jr. (2005) A magnesian granulite clast in lunar meteorite ALHA81005. 68th Annual Meeting of the Meteoritical Society, abstract no. 5278.

Maloy A. K. and Treiman A. H. (2007) Magnesian anorthositic clasts in lunar meteorites ALHA 81005 and Dho 039: Bulk compositions and regional significance. 70th Annual Meeting of the Meteoritical Society, abstract no. 5109.

Marvin U. B. (1983) Some petrologic comparisons between ALHA81005 and lunar highland soil breccias. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 18-19, abstract #6010.

Marvin U. B. (1983) The discovery and initial characterization of Allan Hills 81005: The first lunar meteoriteGeophysical Research Letters 10, 775-778.

Mayeda T. K. and Clayton R. N. (1983) Oxygen isotopic composition of ALHA 81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 20-21, abstract #6011.

Mayeda T. K., Clayton R. N., and Molini-Velsko C. A. (1983) Oxygen and silicon isotopes in ALHA 81005Geophysical Research Letters 10, 799-800.

Morris R. V. (1983) Ferromagnetic resonance and magnetic properties of ALHA81005Geophysical Research Letters 10, 807-808.

Nishiizumi K. (2003) Exposure histories of lunar meteorites. Evolution of Solar System Materials: A New Perspective from Antarctic Meteorites, 104.

Nishiizumi K., Arnold J. R., Klein J., Fink D., Middleton R., Kubik P. W., Sharma P., Elmore D., and Reedy R. C. (1991) Exposure histories of lunar meteorites: ALHA81005, MAC81004, MAC81005, and Y791197Geochimica et Cosmochimica Acta 55, 3149-3155.

Ostertag R. and Ryder G. (1983) ALHA 81005: Petrography, shock, Moon, Mars, Giordano Bruno, and composition. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 23-24, abstract #6013.

Palme H., Spettel B., Weckwerth G., and Wänke H. (1983). Antarctic meteorite ALHA 81005, a piece of the ancient lunar highland crustLunar and Planetary Science XIVAbstracts from the Session on Meteorites from Earth’s Moon, 25-26.

Palme H., Spettel B., Weckwerth G., and Wänke H. (1983) Antarctic meteorite ALHA 81005, a piece from the ancient lunar crustGeophysical Research Letters 10, 817-820.

Palme H., Spettel B., Weckwerth G., and Wänke H. (1983). Antarctic meteorite ALHA 81005, a piece of the ancient lunar highland crust. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 25-26, abstract #6014.

Pieters C. M. (1983) If ALHA 81005 came from the Moon, can we tell from where? Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 27-28, abstract #6015.

Pieters C. M., Hawke B. R., Gaffey M., and McFadden L. A. (1983) Possible lunar source areas of meteorite ALHA81005: Geochemical remote sensing informationGeophysical Research Letters 10, 813-816.

Rahilly K. E. and Treiman A. H. (2009) Granulite clasts of intermediate Mg* in lunar meteorite ALHA 81005: Chemical compositions and origins40th Lunar and Planetary Science Conference, abstract no. 1168.

Rao A. S. P. (1986) Origin of ALHA 81005: Another viewMeteoritics 21, 488-489.

Robinson K. L. and Treiman A. H. (2010) Mare basalt fragments in lunar highlands meteorites: Connecting measured Ti abundances with orbital remote sensing41st Lunar and Planetary Science Conference, abstract no. 1788.

Robinson K. L., Treiman A. H., and Joy J. H. (2012) Basaltic fragments in lunar feldspathic meteorites: Connecting sample analyses to orbital remote sensingMeteoritics & Planetary Science 43, 387-399.

Robinson K. L., Barnes J. J., Tartèse R., Hallis L. J., Franchi I. A., Anand M., and Taylor G. J. (2014) Apatite in Allan Hills 81005 and the origin of water in the lunar magma ocean. 45th Lunar and Planetary Science Conference, abstract no. 2413.

Ryder G. (1983) Glass in ALHA 81005,8 and mare basalts in highlands brecciasMeteoritics 18, 390-391.

Ryder G. and Ostertag R. (1983) ALHA 81005: Petrographic components of the target. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 29-30, abstract #6016.

Ryder G. and Ostertag R. (1983) ALHA 81005: Moon, Mars, petrography, and Giordano BrunoGeophysical Research Letters 10, 791-794.

Sears D. W. G., Benoit P. H., Sears H., Batchelor J. D., and Symes S. (1991) The natural thermoluminescence of meteorites: III. lunar and basaltic meteoritesGeochimica et Cosmochimica Acta 55, 3167-3180.

Simon S. B., Papike J. J., and Shearer C. K. (1983) Petrology and mineral chemistry of ALHA 81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 31-32, abstract #6017.

Simon S. B., Papike J. J., and Shearer C. K. (1983) Petrology of ALHA81005, the first lunar meteoriteGeophysical Research Letters 10, 787-790.

Sutton S. R. (1986) Thermoluminescence of lunar meteorites Yamato-791197 and ALHA-81005. Proceedings 10th Symposium Antarctic Meteorites. Proceedings of the Tenth Symposium on Antarctic Meteorites, 1985. Memoirs of the National Institute of Polar Research, Special Issue 41, 133-139.

Sutton S. R. and Crozaz G. (1983) Thermoluminescence and tracks in ALHA-81005: Constraints on the history of this unusual meteorite. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 33-34, abstract no. 6018.

Sutton S. R. and Crozaz G. (1983) Thermoluminescence and nuclear particle tracks in ALHA 81005: Evidence for a brief transit timeGeophysical Research Letters 10, 809-812.

Takeda H., Mori H., and Tagai T. (1986) Mineralogy of Antarctic lunar meteorites and differentiated products of the lunar crustProceedings of the Tenth Symposium on Antarctic Meteorites, 1985. Memoirs of the National Institute of Polar Research, Special Issue 41, 45-57.

Treiman A. H. and Drake M. J. (1983) Meteorite from the moon: Petrology of terrae clasts and one mare clast in ALHA 81005,9. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 35-36, abstract no. 6019.

Treiman A. H. and Drake M. J. (1983) Origin of lunar meteorite ALHA 81005: Clues from the presence of terrae clasts and a very low-titanium mare basalt clastGeophysical Research Letters 10, 783-786.

Treiman A. H. and Gross J. (2013) Basalt related to lunar Mg-suite plutonic rocks: A fragment in lunar meteorite ALH 81005. 76th Annual Meeting of the Meteoritical Society, abstract no. 5183.

Treiman A. H., Maloy A. K., and Shearer C. K. Jr. (2008) Magnesian anorthositic granulite: An abundant, significant, and poorly understood lunar rock type of the lunar highlands. NLSI Lunar Science Conference, LPI Contribution No. 1415, abstract no. 2112.

Treiman A. H., Maloy A. K., Shearer C. K. Jr., and Gross J. (2010) Magnesian anorthositic granulites in lunar meteorites Allan Hills A81005 and Dhofar 309: Geochemistry and global significanceMeteoritics & Planetary Science 45, 163-180.

Tuniz C., Pal D. K., Moniot R. K., Savin W., Kruse T. H., Herzog G. F., and Evans J. C. (1983) Recent cosmic ray exposure history of ALHA 81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 37-38, abstract no. 6020.

Tuniz C., Pal D. K., Moniot R. K., Savin W., Kruse T. H., Herzog G. F., and Evans J. C. (1983) Recent cosmic ray exposure history of ALHA 81005Geophysical Research Letters 10, 804-806.

Verkouteren R. M., Dennison J. E., and Lipschutz M. E. (1983) Siderophile, lithophile and volatile trace elements in Allan Hills A81005. Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 39-40, abstract no. 6021.

Verkouteren R. M., Dennison J. E., and Lipschutz M. E. (1983) Siderophile, lithophile and mobile trace elements in the lunar meteorite Allan Hills 81005Geophysical Research Letters 10, 821-824.

Warren P. H. and Kallemeyn G. W. (1986) Geochemistry of lunar meteorite Yamato-791197: Comparison with ALHA81005 and other lunar samplesProceedings of the Tenth Symposium on Antarctic Meteorites, 1985. Memoirs of the National Institute of Polar Research Special Issue 41, 3-16.

Warren P. H. and Kallemeyn G. W. (1987) Geochemistry of lunar meteorite Yamato-82192: Comparison with Yamato-791197, ALHA81005, and other lunar samplesProceedings of the Eleventh Symposium on Antarctic Meteorites, 1986. Memoirs of the National Institute of Polar Research, Special Issue 46, 3-20.

Warren P. H. and Kallemeyn G. W. (1991) Geochemical investigations of five lunar meteorites: Implications for the composition, origin and evolution of the lunar crustProceedings of the NIPR Symposium on Antarctic Meteorites 4, 91-117.

Warren P. H., Taylor G. J., Keil K. (1983) Regolith breccia ALHA 81005: Evidence of lunar origin, and nature of pristine and nonpristine clastsLunar and Planetary Science XIV, 828-829.

Warren P. H., Taylor G. J., Keil K. (1983) ALHA 81005: a meteorite from the moon — But can we rule out Mercury? Lunar and Planetary Science XIV, Abstracts from the Session on Meteorites from Earth’s Moon, p. 41-42, abstract no. 6022.

Warren P. H., Taylor G. J., Keil K. (1983) Regolith breccia Allan Hills A81005: Evidence of lunar origin and petrography of pristine and nonpristine clastsGeophysical Research Letters 10, 779-782.

Warren P. H., Jerde E. A., and Kallemeyn G. W. (1989) Lunar meteorites: siderophile element contents, and implications for the composition and origin of the MoonEarth and Planetary Science Letters 91, 245-260.

Yanai K. and Kojima H. (1991) Varieties of lunar meteorites recovered from AntarcticaProceedings of the NIPR Symposium on Antarctic Meteorites 4, 70-90.

Lunar Meteorites | List of Lunar meteorites