A NASA research team of scientists at the Johnson Space Center and at Stanford University has found evidence that strongly suggests primitive life may have existed on Mars more than 3.6 billion years ago. Below are video and animation clips related to this discovery.
Between 3.6 billion and 4 billion years ago, when Mars was warmer and wetter, water penetrated fractures in the subsurface rock. Saturated with carbon dioxide from the Martian atmosphere, carbonate minerals were deposited in the fractures. Living organisms also may have assisted in the formation of the carbonate, and were fossilized. Then, 16 million years ago, a huge comet or asteroid struck Mars, ejecting a piece of the rock. For millions of years, the rock floated through space, falling in Antarctica 13,000 years ago as a meteorite.
Scenes of meteorite ALH84001 being processed in the Lyndon B. Johnson Space Center's Meteorite Processing Laboratory using a special glovebox and airlock to prevent contamination.
Planetary Scientists Dr. David McKay, Dr. Everett Gibson and Dr. Kathie Thomas-Keprta study slides of meteorite ALH84001 using a high-resolution scanning electronic microsope at JSC.
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High-resolution scanning electron microscope images of possible microscopic fossils, part of an array of indirect evidence found by NASA research, appear to indicate primitive life may have existed on Mars more than 3.6 billion years ago. The fossils were found in an ancient meteorite, designated ALH04001, which is believed to be of Martian origin.
Mars Life from Mars: The Discovery