The
details of an outflow channel in Ares Valles show the site of catastrophic
flooding on Mars, as seen by the Mars Reconnaissance Orbiter.
Sometime
in the past, water released from the subsurface of so-called “chaotic terrain”
to the south of this channel. Impact craters on the channel provide a way for
scientists to estimate the age of the flooding event by roughly matching the
number of craters to age. However, the channel bottom may also have been
covered by younger material such as lava. Sand dunes have likewise formed since
the flooding ceased.
No
evidence has emerged of recent running water on the surface of Mars, although
scientists believe liquid water may exist beneath the surface. The Phoenix Mars
Lander is currently starting
to dig near the North Pole for ice and soil samples, so that scientists can
study that history of water on Mars.
— NASA/JPL/University of Arizona and SPACE.com
Staff
Credit: NASA/JPL/University
of Arizona
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