Methane on Mars:Mars Methane Detection and Variability at Gale Crater

By Matthew Polacek

Methane Production

Atmospheric CH4 on Earth Biological sources

Methanogens Abiotic sources

UV degradation Geothermal Production Etc.,

Detection of Methane on Mars Early Measurements

Canada-France-Hawaii telescope NASA IRTF PFS MEX TES

Indications of global averages and localized plumes of methane

Modeling Methane on Mars Plume findings are questionable

Variability in measurements Lack of supporting evidence

Tunable Laser Spectrometer Increased accuracy of the TLS at

SAM on the Curiosity Rover Two channel tunable laser

spectrometer Channel 1, 2.78 microns Channel 2, 3.27 microns

Observations

Note: 1-sol=24 hours 37.5 minutes Data from 605 sols 11 direct ingest measurements and

2 methane enrichment experiments Three groups

Low-methane direct ingest Low-methane enrichment runs High-methane direct ingest

Analysis

Exogenous organics IDP and comets

Modeling UV/CH4 conversion rate 2.2 ppbv model vs. .7 ppbv actual

High-methane results No quantitative correlation

Source:

Mars methane detection and variability at Gale crater Christopher R. Webster et al. Science 347, 415 (2015);

DOI: 10.1126/science.1261713