Submitted on August 28, 2008
Accepted on January 6, 2009
Strong Release of Methane on Mars in Northern Summer 2003
Michael J. Mumma 1*, Geronimo L. Villaneuva 2, Robert E. Novak 3, Tilak Hewagama 4, Boncho P. Bonev 2, Michael A. DiSanti 5, Avi M. Mandell 5, Michael D. Smith 5
1 NASA Goddard Space Flight Center, Mailstop 690.3, Greenbelt, MD 20771, USA.
2 Department of Physics, Catholic
University of America, Washington, DC 20008, USA.; NASA Goddard Space Flight Center, Mailstop 693, Greenbelt, MD 20771, USA.
3 Department of Physics, Iona College, New Rochelle, NY 10801, USA.
4 NASA Goddard Space Flight Center, Mailstop 693, Greenbelt, MD
20771, USA.; Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA.
5 NASA Goddard Space Flight Center, Mailstop 693, Greenbelt, MD
20771, USA.
* To whom correspondence should be addressed.
Michael J. Mumma , E-mail: michael.j.mumma{at}nasa.gov
Living systems produce more than 90% of Earth's atmospheric methane; the balance is of geochemical origin. On Mars, methane could be a signature of either origin. Using high-dispersion infrared spectrometers at three ground-based telescopes, we measured methane and water vapor simultaneously on Mars over several longitude intervals in (northern) early- and late-summer 2003 and near vernal equinox 2006. When present, methane occurred in extended plumes and the maxima of latitudinal profiles imply that the methane was released from discrete regions. At northern mid-summer, the principal plume contained ~19,000 metric tons of methane and the estimated source strength (
0.6 kg s-1) was comparable to that of the massive hydrocarbon seep at Coal Oil Point (Santa Barbara, CA).