Explanation:
Why is there methane on Mars?
No one is sure.
An
important confirmation that methane exists in the atmosphere of Mars occurred last week, bolstering
previous controversial claims made as early as
2003.
The confirmation was made
spectroscopically using
large
ground-based telescopes by finding precise colors absorbed on
Mars that match those absorbed by methane on Earth.
Given that methane
is destroyed in the
open martian air in a matter of years,
the present existence of the fragile gas
indicates that it is currently being released, somehow,
from the surface of Mars.
One prospect is that
microbes
living underground are creating it, or created it in the past.
If true, this opens the exciting possibility that
life might be present under the surface of Mars even today.
Given the present data, however, it is also
possible that a purely geologic process, potentially involving
volcanism or
rust
and not involving any life forms, is the methane creator.
Pictured above is an image of Mars superposed with a
map of the recent methane detection.
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