Information AboutMars Meteorite |
| CATEGORIES ABOUT MARS METEORITE | |
| mars | |
| meteorites | |
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Note that this does not refer to meteorites actually found ''on'' Mars, such as Heat Shield Rock . COMPOSITION Mars meteorites include three rare groups of , India ( 1865 ), El-Nakhla , Egypt ( 1911 ), and Chassigny , Haute-Marne , France ( 1815 ) respectively. One of the shergottites, known as ALH84001 , received a lot of attention after an electron microscope revealed structures that were considered to be the Fossilized remains of Bacteria -like Lifeforms . As of 2005 however, most experts agree that the Microfossils are not indicative of life, but of contamination by earthly Biofilm s. It has not yet conclusively been shown how they formed. ALH84001 is much older than the others in the SNC group - dating back to the original formation of Mars about 4.5 billion years ago. In this respect, it resembles a typical meteorite rather than the other SNC's, which all appear to be formed less than 1.3 billion years ago. All the meteorites are Igneous Rock s. Lherzolitic shergottites (one from Antarctica , 2 from California ) are identified by their Deuterium / Hydrogen ratios. The crystals appear to be 154-187 million years old and they appear, from Cosmic Ray analysis, to have spent 2.5 to 3.6 million years in space. There are also Basalt ic shergottites, some of which appear (from the presence of hydrated Carbonate s and Sulfate s) to have been exposed to liquid water prior to injection into space. In March 2004, it was suggested that the unique Kaidun Meteorite landed on March 12, 1980 in Yemen , may have originated on the Martian moon of Phobos . POSSIBLE EVIDENCE OF LIFE Possible evidence of life has been hypothesized in three meteorites.
In August 2002 , a NASA team led by Thomas-Keptra published a study indicating that 25% of the magnetite in ALH 84001 occurs as small, uniform-sized crystals in a crystal form that, on Earth, is associated only with biologic activity. The remainder of the material appears to be normal inorganic magnetite. The extraction technique did not permit determination as to whether the possibly biologic magnetic was organized into chains as would be expected. REFERENCES |
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