for National Geographic News
Dust storms on Mars appear to be creating a snow of bleachlike chemicals that make their way into the planet's soilrendering life as we know it impossible on the red planet's surface, scientists report.
The announcement comes close to the tenth anniversaryAugust 6, 1996of the now discredited claim by NASA scientists that they had discovered evidence of life on Mars inside a Martian meteor found in Antarctica.
The toxic chemicals cited in the new study, including hydrogen peroxide, are created by the action of static electricity generated by dust devils.
Dust devils are swirling vortexes that can tower several miles high and a quarter-mile (about a half a kilometer) wide at the base. They're not tornados, but on Earth they can pack enough punch to knock people off their feet.
Frequently seen on Mars, dust devils have unexpectedly extended the lives of NASA rovers by blasting light-blocking dust off their solar panels. (See "Mars Rovers Exceed 1-Year MarkAnd Expectations" [January 24, 2005].)
The new research applies what is known about Earthly dust devils to conditions in the thinner Martian atmosphere.
"We spent years chasing dust devils in the Arizona desert with a special instrumented truck," said Gregory Delory, a physicist from the University of California, Berkeley. Delory is the lead author of one of two papers on the subject published in the most recent issue of the journal Astrobiology.
The researchers found that Martian dust devils would create large amounts of static electricity.
"It's analogous to rubbing your feet against the carpet and shocking someone," Delory said.
The static fields aren't strong enough to produce lightning bolts, but they do produce sparks.
(See a gallery of Mars images.)
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