March 27, 2009

Could Mud Volcanoes Exist On Mars?

The answer to whether or not Mars is hospitable to life could lie beneath the surface, experts from NASA's Johnson Space Center in Houston said on Thursday.

During the Lunar and Planetary Science Conference in The Woodlands, Texas, Carlton Allen and Dorothy Oehler presented images taken by NASA's Mars Odyssey spacecraft that show several mounds across the surface of the Red Planet, which they suggest could actually be mud volcanoes.

If Allen and Oehler's theory were true, the discovery of mud volcanoes on Mars could provide new clues into the possibility of life on the planet.

Mud volcanoes are common on Earth. They have been found at more than 40 sites on land and more than 20 locations under the sea, according to BBC News. The largest grouping of them can be found in Azerbaijan and the Caspian Sea.

Mud volcanoes could be harboring liquid water deep below the surface, and could also spew rocks from below the surface, which could be discovered and analyzed by robotic probes.

Researchers also revealed infrared images that show the domes cool quickly at night in comparison to surrounding rock, suggesting that they could be composed of sediment.

Allen and Oehler studied alongside David Baker of Brown University using instruments on NASA's Mars Reconnaissance Orbiter (MRO) to study the mounds, which are found in the northern region of the planet called Acidalia Planitia.

Mud volcanoes are formed when pressurized gas and liquid deep down reaches the surface, resulting in a spew of liquid, mud, rocks and gases.

"In Azerbaijan, there is so much methane coming out that they can catch fire," Dr Allen told BBC News.

Scientists have observed the presence of methane in the atmosphere of Mars. The possibility of mud volcanoes on the surface of the planet could help provide an explanation.

Allen said the domes could have formed in the last 10 million years, but found no proof that they may still be active.

During the conference on Wednesday, a separate team of researchers argued that the discovery by NASA's Phoenix probe showing that perchlorate salts exist within the soil of Mars adds credence to the idea of liquid water on the planet.

Some researchers believe that perchlorate salts, which can keep liquid at temperatures of minus 70C, may be mixed with ice to form pools of liquid water on the planet.


Image Caption: High-albedo dome in Acidalia Planitia


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