ALH 84001
Geological analysis of ALH 84001 has revealed something of its history. It formed originally from molten lava which possibly issued from an ancient Martian volcano, about 4.5 billion years ago. Some 4 billion years ago, it was heated again and deformed by a strong shock, probably resulting from the nearby impact of an asteroid or large meteorite. Then, about 3.6 billion years ago, some kind of liquid flowed through the rock and deposited rounded globules of carbonate minerals. About 15 million years ago, ALH 84001 is believed to have been hurled from the surface of Mars when an asteroid or comet collided obliquely with the planet. Finally, it became the center of a major controversy in 1996 when scientists at the NASA Johnson Space Center, led by David S. McKay, claimed that they had found inside the meteorite very small fossils and other evidence of Martian biological activity centered around the carbonate deposits. Related categories MARS TOPICS FAMOUS METEORITES METEORS AND METEORITES ASTROBIOLOGY Archived news Martian magnetite and biogenicity: the final word? (May 15, 2002) Fresh doubts over Martian magnetite claims (Nov 20, 2001) ALH 84001: Does it really contain life signs? (Apr 2, 2001) Magnetities in ALH84001: Biogenicity debate continues (Mar 17, 2002) Magnetite in Mars meteorite biogenic conclude researchers (Dec 13, 2000) External site ALH 84001 papers (Lunar and Planetary Institute) Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |