Aug. 15, 2006 — The ambitious Viking missions to Mars, dispatched in the 1970s to search for life on the Red Planet, left a few puzzles for researchers to ponder, including a soil experiment that showed unmistakable signs of chemical activity.
Followup studies determined the triggering agent was, disappointingly, not organic matter. The mystery lay dormant for 30 years until recently when a team of scientists found proof of another interloper: Martian dust devils.
Whipped by strong winds, mini-cyclones of swirling dust regularly dance across the face of Mars, generating fields of static electricity as particles rub against each other and cast off positive and negative charges.
Scientists believe the electricity may produce reactive chemicals that build up in the Martian soil, a theory that would explain Viking's puzzling results.
"Our calculations indicate that once these electric fields are produced by dust storms on Mars, they free more electrons from atoms and molecules in the thin Martian atmosphere," said Gregory Delory, a senior fellow at the University of California Berkeley Space Science Laboratory.
"These electrons then collide with and break apart molecules such as water and carbon dioxide, creating new chemical products that continue to react with other constituents in Mars' atmosphere."
