Low Upper Limit to Methane Abundance on Mars
Abstract
By analogy with Earth, methane in the Martian atmosphere is a potential signature of ongoing or past biological activity. During the past decade, Earth-based telescopic observations reported "plumes" of methane of tens of parts per billion by volume (ppbv), and those from Mars orbit showed localized patches, prompting speculation of sources from subsurface bacteria or nonbiological sources. From in situ measurements made with the Tunable Laser Spectrometer (TLS) on Curiosity using a distinctive spectral pattern specific to methane, we report no detection of atmospheric methane with a measured value of 0.18 ± 0.67 ppbv corresponding to an upper limit of only 1.3 ppbv (95% confidence level), which reduces the probability of current methanogenic microbial activity on Mars and limits the recent contribution from extraplanetary and geologic sources.
Additional Information
© 2013 American Association for the Advancement of Science. 8 July 2013; accepted 5 September 2013; Published online 19 September 2013. The research described here was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA). Data described in the paper are further described in the supplementary materials and have been submitted to NASA's Planetary Data System under an arrangement with the Mars Science Laboratory project.Attached Files
Supplemental Material - Webster.SM.pdf
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Additional details
- Eprint ID
- 42376
- DOI
- 10.1126/science.1242902
- Resolver ID
- CaltechAUTHORS:20131112-104640207
- NASA/JPL/Caltech
- Created
-
2013-11-12Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences (GPS)