The proximity and similarity of Mars to Earth have led to intense exploration programs spanning over 40 years, driven by fundamental questions regarding the formation of the solar system and planets, and the evolution of life. In recent years there has been intense interest in understanding the composition of the atmosphere of Mars since the existence of certain compounds with relatively short lifetimes suggest active production mechanisms. Of particular interest has been methane, which is thought to have a lifetime on the order of 300 to 600 years, so its presence must indicate a strong active source to maintain itself. The most likely sources may be geological processes such as serpentinization or from biological activity.
The Mars Atmospheric Trace Molecule Occultation Spectrometer (MATMOS) investigation was a collaboration between the Canadian Space Agency (CSA) and NASA’s Jet Propulsion Laboratory. It was intended to fly on the European Space Agency’s ExoMars Trace Gas Orbiter until NASA withdrew from the ExoMars mission. The MATMOS instrument is a Michelson interferometer similar to the CSA’s Atmospheric Chemistry Experiment Fourier Transform Spectrometer.
My talk will briefly introduce Mars and the ExoMars mission, then discuss our measurement technique and its advantages. Applying this technique to Mars introduces special challenges that are the focus of my studies. These include a method to measure the temperature and pressure vertical profiles of the atmosphere, and a study on how the high quantities of airborne dust can affect the observations. Dust not only attenuates the signal incident on the instrument, but can also cause the source intensity to vary during a single scan. This affects the shape of the recorded spectrum and must be well understood to obtain the best measurements of the Martian atmosphere.