NASA orbiter to hunt for source of Martian methane in 2016

London, March 6 (ANI): NASA is planning to launch an orbiter in 2016 that could map methane on Mars and help settle whether the gas has a biological or geological origin.

According to a report in New Scientist, the orbiter will fly on its own or with the European Space Agency's (ESA's) ExoMars rover.

NASA will launch the orbiter in 2016 to help boost telecommunications around the planet as existing orbiters age.

A rover or lander may follow in 2018, as a next step in the path to one day returning samples of Martian rocks and soil to Earth.

Though the exact payload and budget of the 2016 probe are not yet set, but a team of researchers has presented a vision of the probe's basic payload that could clear up the picture of how methane on Mars is distributed and where it comes from.

Ground-based observations of the Red Planet led by Michael Mumma of NASA's Goddard Space Flight Center suggest methane on Mars actually stems from a few hotspots that could be linked to underground pockets of gas created by the interaction of water with volcanic rock, or perhaps, by methane-producing microbes.

But, some remain unconvinced of the hotspot result, arguing that the gas should be evenly spread since it moves quickly and seems to have a long lifetime in the atmosphere.

The 2016 orbiter could help determine whether there are indeed methane hotspots.

One idea is to use a spectrometer to look through the Martian atmosphere when the Sun passes behind the planet - an event called a 'solar occultation'.

By measuring how much sunlight is absorbed by the atmosphere during the occultations, the spectrometer could detect the concentration of gases in the atmosphere to a sensitivity of several parts per trillion.

"It has more than enough accuracy to test Mumma's report," said Jim Kasting of Pennsylvania State University in University Park, and a member of the 2016 probe's Science Definition Team.

"You will also get better spatial and temporal accuracy of the distribution of methane over the planet," Kasting told New Scientist.

The case for a biological origin for the gas would be strengthened if there is an overabundance of methane laden with the isotope carbon-12, which life prefers to process over heavier isotopes.

If, however, the atmosphere also contains heavier hydrocarbons uch as ethane, which life as we know it cannot produce, that ould point to a geological source for the methane. (ANI)