Detection of Methane in the Atmosphere of Mars
Abstract
We report a detection of methane in the martian atmosphere by the Planetary Fourier Spectrometer onboard the Mars Express spacecraft. The global average methane mixing ratio is found to be 10 ± 5 parts per billion by volume (ppbv). However, the mixing ratio varies between 0 and 30 ppbv over the planet. The source of methane could be either biogenic or nonbiogenic, including past or present subsurface microorganisms, hydrothermal activity, or cometary impacts.
Supplementary Material
File (formisano.som.pdf)
References and Notes
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The PFS was built at the Istituto di Fisica dello Spazio Interplanetario of the Istituto Nazionale di Astrofisica, and the investigation is being funded by the Italian Space Agency (ASI) in the context of the Italian participation in the Mars Express mission of the European Space Agency. S.A. acknowledges support from NASA/Jet Propulsion Laboratory for participation in the Mars Express project. We are grateful to V. Cottini for a number of synthetic spectra computations and to A. Maturilli for the mapping figure.
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Published In
Science
Volume 306 | Issue 5702
3 December 2004
3 December 2004
Copyright
American Association for the Advancement of Science.
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Submission history
Received: 21 June 2004
Accepted: 18 October 2004
Published in print: 3 December 2004