The Mars Global Surveyor spacecraft, which has been orbiting the Red Planet since 1997, was relegated to the media shadows early this year when it's new sister craft, Mars Odyssey, began returning pictures and found intriguing evidence for water ice near the surface of Mars.

However, Surveyor, also called MGS, is alive and well and still producing remarkable photographs with its onboard Mars Orbiter Camera.

Most of the pictures do not individually provide for important findings, but many are interesting nonetheless.

One new picture provides insight into how winds sculpt the surface. The picture shows a field of dark sand dunes on the floor of Kaiser Crater in the Noachis Terra region of Mars. The steepest slopes on each dune, called slip faces, point toward the east, indicating that the strongest winds that blow across the floor of Kaiser move sand in this direction, said scientists at Malin Space Science Systems, which operates the camera for NASA.

Large ripples are probably places where shifting sand is burying some dunes and revealing others, the researchers said.

Another type of smaller ripple pattern is seen on the margins of the dunes and where dunes coalesce. These are probably coarse sediments moving with the dunes.

[In other recent pictures, researchers claimed to see signs of life dotting Martian dunes.]

A second image shows gullies carved from a specific layer in the wall of a smaller and ancient crater within the much larger crater, Kaiser. Several dark, and in some places squiggly streaks are visible and are thought to have been formed by the passage of dust devils -- a Mars equivalent of generally mild tornadoes -- that removed or disrupted a thin coating of dust from the surface.

Such streaks commonly form at Martian middle latitudes in late spring and early summer. The gullies in the crater wall were likely eroded by a fluid, perhaps water, Malin scientists say.

A third picture reveals an octopus-like pattern of mesas and troughs in the Nilosyrtis region of Mars. Valleys or troughs of similar depth and width separate the flat-topped mesas, something like what exists in the American Southwest.

Researchers say the valley floors are covered by a material that has subsequently developed thin cracks and collapse pits aligned along some of these cracks. A few outcrops of layered material occur in the valleys as well.

The valleys probably originally formed by faulting, when plates of the surface shifted.

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