Sarah Chamberlain

Mapping Martian Atmospheric Pressure with Ground-Based Near Infrared Spectroscopy

We present images of Mars obtained in the 2.0 μm CO2 band with the United Kingdom Infrared Telescope (UKIRT). The images reveal topographic features of the Martian surface that are usually invisible in direct albedo images at visible or IR wavelengths, but agree remarkably well with the topography of the planet as mapped by the MOLA instrument on Mars Global Surveyor. The CO2 band depth is a measure of the absorbing column of CO2 and hence determined primarily by the surface atmospheric pressure. The surface pressure variations are detected with a sensitivity of 4–5 Pa. We compare our data with radiative transfer models and find that the measured CO2 variation with pressure is consistent with the models. We discuss the possibility that similar observations might be used to observe atmospheric pressure changes due to Martian weather systems.

Improving the chance of finding fossil microbes on Mars

All life on Earth requires the presence of liquid water. Evidence that Mars once had liquid water for extended periods of time is growing and is keeping alive the possibility that life may once have started on Mars. We are using infrared spectroscopy of Mars to search for minerals indicative of the past presence of liquid water. If we can locate regions containing such minerals, these would be promising locations to search for fossil microbes.