This is a picture of the meteorite ALH84001.
Click on image for full size
The possible discovery of Life on Mars
In July, 1996 a team of scientists said that they had discovered
possible fossils of bacteria
in a meteorite named ALH84001 that came from Mars. It was found in Antarctica in 1984 after having landed there 12,000 years ago. After a couple years of study, it appears that the scientists were wrong.
Some chemicals found in the meteorite look like chemicals created by life on Earth. These same chemicals can also be created without the help of life.
Small balls or spheres were seen in the meteorite which the
scientists in 1996 thought were the fossilized remains of bacteria. However, they are roughly 1000 times smaller than the smallest life known on Earth. This seems much too small to be life. Other pieces of evidence turned out to have come from Earth after the rock landed here, and not from Mars at all.
The environment of Mars in the
past was very different than it is today. Conditions then may have been favorable for the existence of life. Its too bad, but the Mars meteorite just isn't the proof that some people hoped it would be.
Shop Windows to the Universe Science Store!Traveling Nitrogen
is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.
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