Was there ever life on Mars? Scientists have debated this question for years. Last week researchers revealed new evidence that life may have once existed on the Red Planet.

Scientists at the Johnson Space Center in Houston, Texas, examined a 4.6 billion-year-old meteorite from Mars. The meteorite had landed in Antarctica. Using a powerful microscope, they found tiny crystals linked together in a chain. Crystals can be formed two ways: by a chemical process or by living organisms. The shape of the chains in the meteorite suggests they could only have been formed by a living creature, perhaps something similar to a bacterium.

"I am convinced that this is supporting evidence for the presence of ancient life on Mars," says Kathie Thomas-Keptra, who led the study. "If it existed there at one time, we could even expect it to exist today," she adds. Not all scientists agree with her conclusion, but others are eager to do more research on the Mars rock.

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March 9, 2001 World Report