This month, a team of four UK scientists, including Claire Cousins from the UK Centre for Astrobiology (UKCA) based at the University of Edinburgh, went to Iceland to test a prototype of the Panoramic Camera (PanCam) instrument, which will form a major component of the European Space Agency’s 2018 ExoMars rover.
Sending a robotic rover to explore the surface of Mars is a significant challenge, and an endeavour that requires many years of preparation, particularly of the various instruments that will become part of the rover payload.
Minerals on Mars
Dr Cousins, along with colleagues from Aberystwyth University, Birkbeck College, and University College London, spent two weeks working at the Krafla volcanic region of northern Iceland. Here, the terrain is characterised by basaltic rocks that have undergone extensive aqueous alteration, producing many of the same mineral assemblages that have been identified on Mars. Such terrains are evidence of environments that, at least on Earth, are home to thriving microbial communities. This makes this location an ideal site for testing instruments that will be on future astrobiology missions, such as the ExoMars mission, which will need to identify rocks and sediments that were produced in past habitable environments. Volcanic processes are particularly relevant to past Martian environments, as volcanism has been so prevalent throughout Martian history.
The PanCam instrument does more than just image the rover’s surroundings. Two wide-angle cameras set 50cm apart provide stereo vision, meaning the terrain can be imaged in 3D. It also has the ability to view the terrain at many different wavelengths, from the visible to the near-infrared (VNIR), providing information on the spatial distribution of particular mineral types. Finally, PanCam has a High Resolution Camera, which can provide detailed images of particular features on a distant rocky target. All together, these various data products enable planetary scientists to carry out geological investigations of the surrounding terrain, which is crucial for target selection (ie where to send the rover to investigate further) when exploring the Martian surface.
The aim of the Iceland fieldwork was to test PanCam at sites where the team could take samples (for laboratory analysis), and other in-situ data, in order to establish the scientific capabilities of the instrument. These samples will be analysed with XRD and Raman Spectroscopy to identify their mineralogy, and with VNIR reflectance spectroscopy to see how their spectral properties compare with PanCam multispectral data. Additionally, in-situ reflectance spectra were measured from PanCam targets using a field reflectance spectrometer loaned from the NERC Field Spectroscopy Facility, also based at the University of Edinburgh in the School of Geosciences. All this information will eventually feed into the PanCam data processing pipeline, ultimately fine-tuning the instrument and its software so it can be used confidently on the surface of Mars.
"Testing instruments on these types of terrains is the closest we can get to simulating the Martian surface geology. This was a very successful trip, not least due to the combined expertise of the team that included geology, remote sensing and engineering. I'm hopefull it'll lead to more Mars analogue field-testing of future instrument concepts." Claire Cousins, UK Centre for Astrobiology
Find out more
More details of this research, including an up-to-date web blog detailing the fieldwork itself, can be found at http://clairecousins.wordpress.com/category/fieldwork/iceland/.