Post by Chicago Astronomer - Astro Joe on Aug 17, 2006 20:44:04 GMT -6
Findings Suggest Jets Bursting From Martian Ice Cap
Every spring brings violent eruptions to the south polar ice cap of Mars, according to researchers interpreting new observations by NASA's Mars Odyssey orbiter
"If you were there, you'd be standing on a slab of carbon-dioxide ice," said Phil Christensen of Arizona State University, Tempe, principal investigator for Odyssey's camera. "All around you, roaring jets of carbon dioxide gas are throwing sand and dust a couple hundred feet into the air."
You'd also feel vibration through your spacesuit boots, he said. "The ice slab you're standing on is levitated above the ground by the pressure of gas at the base of the ice."
Dark spots (left) and 'fans' appear to scribble dusty hieroglyphics on top of the Martian south polar cap. Image credit: NASA/JPL/Malin Space Science Systems.
The team began its research in an attempt to explain mysterious dark spots, fan-like markings, and spider-shaped features seen in images that cameras on Odyssey and on NASA's Mars Global Surveyor
The dark spots, typically 15 to 46 meters (50 to 150 feet) wide and spaced several hundred feet apart, appear every southern spring as the sun rises over the ice cap. They last for several months and then vanish -- only to reappear the next year, after winter's cold has deposited a fresh layer of ice on the cap. Most spots even seem to recur at the same locations.
An earlier theory proposed that the spots were patches of warm, bare ground exposed as the ice disappeared. However, the camera on Odyssey, which sees in both infrared and visible-light wavelengths, discovered that the spots are nearly as cold as the carbon dioxide ice, suggesting they were just a thin layer of dark material lying on top of the ice and kept chilled by it.
More here: www.physorg.com/news75049938.html
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To my untrained eye...it looks organic.