NASA announces Mars 2020 rover payload
On July 31, NASA announced the roster of instruments that would hitch a ride on board its planned rover to the red planet in 2020. John Grunsfeld, astronaut and associate administrator for the NASA Science Mission Directorate, Headquarters, Washington, said the instruments would extend the search for life in Mars’s past, conduct geological and environmental investigations to that end, equip it to cache martian material for future explorers to bring back to Earth, and conduct studies that will help the agency land humans on Mars.
Michael Meyer, lead scientist with the Mars Exploration Program, detailed the instruments that would go on board the rover. Going from mast to the body and then to the arm, he laid out seven major instruments developed by over 50 institutions from around the world. Meyer said their guiding principle is that no measurement will be done by only one instrument, that whether it was the chemistry, mineralogy or geology that was being studied, the instruments would overlap, provide multiple perspectives on readings and help constrain error.
The mast would hold the cameras called Mastcam Z and SuperCam. Mastcam Z will be a binocular with zoom capable of rapidly developing terrain models. According to Meyer, the Curiosity rover is slowed down by having to reassess its surroundings once every 10 m for rocky outcrops or surfaces that might threaten it. Mastcam Z will be equipped to plot out greater distances at once. SuperCam, with a significant contribution from France, is the 2020 rover’s counterpart of Curiosity’s ChemCam, which ionizes martian soil samples and studies the missions for their mineral composition. Additionally, SuperCam will also boast a visible and near-infrared spectrometer to make observations at those wavelengths. It will be a remote-sensing instrument to help make important decisions about soil composition and the presence of organic material.
The rover’s body will hold instruments called MOXIE, MEDA and RIMFAX, and MOXIE takes the cake for innovation. It will attempt to extract carbon dioxide from Mars’s atmosphere, break it down and produce pure oxygen. Meyer said that the oxygen could comprise rocket fuel for future human explorers. However, Bill Gerstenmaier, associate administrator for the NASA Human Exploration and Operations Directorate, implied that that claim was exaggerated, saying scientists would first study at what rate and efficiency oxygen could be produced and if its presence could pose any risks.
MEDA, from Spain, would be the on-board weather station, providing data on atmospheric conditions. RIMFAX will give the 2020 rover the ability to ‘see’ below Mars’s surface. It’s a ground-penetrating radar that can go up to 0.5 km downward and and help connect outcrops on the surface with geological formations beneath them.
Two instruments will ride the rover’s arm: PIXL, the interfacing instrument that tells scientists where the action is at smaller scales based on samples the other instruments have analysed, and SHERLOC, a deep-UV instrument adept at studying organic material.
Even though all instruments will be capable of performing multiple analyses, the flow of ‘work’ according to Meyer is roughly ordered as: mast instruments look around the landscape for interesting things, mineralogies that might be best at preserving biosignatures and recent outcrops; arm instruments study samples at finer scales and look at features that might’ve attracted microbial growth in the past; then, based on data, scientists decide whether they want to drill and cache that sample for posterity.
Mars-2020 is being envisaged as Curiosity’s next step with bifurcated goals: landing humans on Mars by studying local geological and radiological properties, and looking for life in its past and helping conduct more sophisticated studies on soil samples.
Like with MOXIE, Meyer explained that the caching of samples would also be proof-of-concept: NASA definitely intends to cache samples but isn’t yet sure what it will do with them. Grunsfeld quoted Carl Sagan to say that if they did find signs of life, they’d also have to muster extraordinary evidence to back up their claim – evidence that could only be established if the samples were subjected to tougher tests on Earth. Meyer concluded by adding that the one-metric-ton rover would be landed on Mars the same way Curiosity was – with the sky-crane.
