The Gullies Of Mars
Explanation:
The
recently
revealed gullies on Mars are rare.
But
they may prove to be sites of present day, near surface,
liquid
water, holding out the tantalizing possibility of
martian
life.
Too small to have been seen by
past
Mars orbiters,
these disconcerting landforms were found in
only about 250 out of more
than 20,000 high resolution images from the operating
Mars
Global Surveyor spacecraft.
Gullies found so far are located away from
the martian
equatorial region at middle and high
latitudes (predominately in the south) and on poleward facing slopes.
They are disconcerting because researchers have a compelling
body of evidence that the
martian gullies are related to groundwater
seepage and, like their terrestrial counterparts,
liquid water runoff -- on
a planet whose
surface is thought to be too cold and atmosphere too thin for liquid
water to exist.
The gullies in the three kilometer wide area
pictured above are in the south facing wall of a
crater in southern
Noachis
Terra.
Unblemished by craters and overlaying young surface features,
these and other gullies are
inescapably young themselves.
In fact,
future
monitoring of the martian gullies for
changes could demonstrate whether the flows that formed them
are still active today.
Tomorrow's picture: Saturnday
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
