Mars Orbiter Spots Changes on Red Planet

http://news.yahoo.com/s/ap/20050921/...c/mars_orbiter

PASADENA, Calif. - The Martian surface has undergone dramatic changes in
the last few years with the appearance of new gullies and fresh boulder
tracks, new images released Tuesday show.
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The photos, taken by the orbiting Mars Global Surveyor spacecraft,
suggest that the Red Planet is perhaps more active than previously thought.

The spacecraft, in its ninth year in orbit, spotted two fresh gullies on
a Martian sand dune that were not present in 2002. Scientists think the
gullies might have formed when frozen carbon dioxide trapped by
windblown sand vaporized, releasing gas that allowed the sand to flow
freely.

The spacecraft also took images of boulder tracks at another site that
were not there two years ago. The tracks were probably caused by dozens
of boulders rolling down a slope from strong wind or a quake, scientists
said.

Researchers also noted that impact craters forming since the 1970s
suggest that crater-formation is a slow process, occurring at one-fifth
the pace previously thought.

On Wed, 21 Sep 2005 07:47:40 -0700, szaki wrote:

http://news.yahoo.com/s/ap/20050921/...c/mars_orbiter

PASADENA, Calif. - The Martian surface has undergone dramatic changes in
the last few years with the appearance of new gullies and fresh boulder
tracks, new images released Tuesday show.
ADVERTISEMENT

The photos, taken by the orbiting Mars Global Surveyor spacecraft,
suggest that the Red Planet is perhaps more active than previously thought.

The spacecraft, in its ninth year in orbit, spotted two fresh gullies on
a Martian sand dune that were not present in 2002. Scientists think the
gullies might have formed when frozen carbon dioxide trapped by
windblown sand vaporized, releasing gas that allowed the sand to flow
freely.

The spacecraft also took images of boulder tracks at another site that
were not there two years ago. The tracks were probably caused by dozens
of boulders rolling down a slope from strong wind or a quake, scientists
said.

Researchers also noted that impact craters forming since the 1970s
suggest that crater-formation is a slow process, occurring at one-fifth
the pace previously thought.

Check out the shadowing in both pictures. Looks more like the
"changes" could be just another "Mars Face."
-Rich