spacetoday.net: Mars Express links water and methane

Posted: Tue, Sep 21, 2004, 7:58 AM ET (1158 GMT)
Mars Express in orbit (ESA illustration)

Scientists announced Monday that they have linked traces of methane in the Martian atmosphere with concentrations of ice beneath the Martian surface, raising the possibility that the methane has been generated biologically. The analysis is based on data collected by ESA's Mars Express spacecraft, whose spectrometer has detected traces of methane in the planet's atmosphere. That data showed that both methane and water vapor in the atmosphere are not spread uniformly but instead are concentrated closer to the surface over those regions where NASA's Mary Odyssey spacecraft detected subsurface water ice. This has led scientists to believe that the release of both water ice and methane in the atmosphere are linked, although they don't know enough to determine whether that process is geological or biological in nature. Vittorio Formisano, the scientist who led the study, has also reportedly detected traces of other compounds in the Martian atmosphere that could have biogenic origins, including hydrogen sulfide and formaldehyde, but those results have not yet been published.