| Allan Hills 77005 | |
| Type: | Achondrite (unique)[1] |
| Clan: | Martian meteorite |
| Composition: | ~55% olivine, ~35% pyroxene, ~8% maskelynite and ~2% opaques |
| Shock: | S6[2] |
| Weathering: | A |
| Country: | Antarctica |
| Region: | Allan Hills |
| Observed Fall: | No |
| Found Date: | 29 December 1977 (Japanese National Institute of Polar Research mission)[3] |
| Tkw: | 482.5 g |
Allan Hills 77005 (also known as Allan Hills A77005, ALHA77005, ALH77005 and ALH-77005[4]) is a Martian meteorite that was found in the Allan Hills of Antarctica in 1977 by a Japanese National Institute of Polar Research mission team and ANSMET.[5] Like other members of the group of SNCs (shergottite, nakhlite, chassignite), ALH-77005 is thought to be from Mars.[6]
On discovery, the mass of ALH-77005 was 482.5g. Initial geological examination determined that the meteorite was composed of ~55% olivine, ~35% pyroxene, ~8% maskelynite and ~2% opaques.[7]
In March 2019, researchers reported the possibility of biosignatures in this Martian meteorite based on its microtexture and morphology as detected with optical microscopy and FTIR-ATR microscopy, and on the detection of mineralized organic compounds,[8] [9] [10] suggesting that microbial life could have existed on the planet Mars. More broadly, and as a result of their studies, the researchers suggest Solar System materials should be carefully studied to determine whether there may be signs of microbial forms within other space rocks as well.