(Submitted November 10, 1997)
Is there any water on Mars?
There is water on Mars. More specifically, there is ice in and on the
ground (especially at the polar caps) and water vapor in the atmosphere.
There may be liquid water underground, but liquid water on the surface is
probably very rare and only temporary, requiring weather conditions
(temperatures above freezing, high humidity, and high barometric
atmospheric pressure) which never occur in most places on Mars, and occur
only rarely in others.
It was not always so. In earlier times, the air pressure on Mars was
higher, and you can still see the river beds and other features that water
More information about Mars is at
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