Many scientists believe that Mars could have been home to microbes or other forms of life.
One way to find out for sure: Lasers!
The Mars 2020 rover, currently scheduled for a landing on the Red Planet in early 2021, is equipped with seven instruments; just one, however, is "Super." The SuperCam , placed high on the vehicle’s mast, fires a laser that can analyze rocks – by vaporizing them.
In the summer of 2019, researchers at the Los Alamos National Laboratory tested the instrument's ability to find and image a target, and record resulting spectra emissions from the laser pulse.
Like its predecessor, the "ChemCam," the SuperCam employs a method called laser induced breakdown spectroscopy. Through "LIBS," the Supercam's infrared laser beam heats a targeted material to around 18,000 degrees Fahrenheit – a rock-vaporizing temperature.
A special camera then analyzes the resulting plasma to determine the rocks' chemical makeup.
The Curiosity rover’s “ChemCam,” launched in 2011 and landed in 2012, used an infrared laser beam to learn about Mars rocks. The SuperCam – a kind of ChemCam 2.0 – employs a green Raman spectroscopy laser to excite chemical bonds and produce a specific signal for each element.
NASA will use the SuperCam to find materials like clays and sulfates – minerals that formed in the presence of liquid water and that are therefore possible habitats for life.
The green laser, which can hit a targeted object from up to 20 feet away, also causes some minerals and carbon-based chemicals to emit light, or fluoresce.
Like ChemCam, SuperCam uses artificial intelligence to spot important targets. Analysis from the instrument will help to determine when the rover should collect specific rock samples for further examination.
The SuperCam also added a feature not seen on the ChemCam: A microphone. The resulting audio will pick up the sounds of the Martian atmosphere, as well as help scientists to listen as a laser hits a target. The laser’s popping sound differs depending on a rock’s material properties.
NASA's Jet Propulsion Laboratory (JPL) manages overall operations of the Mars 2020 rover for the NASA Science Mission Directorate at the agency's headquarters in Washington.
The SuperCam’s body unit, which includes spectrometers, control electronics, and software, was developed at Los Alamos National Laboratory in New Mexico.
In an interview below, SuperCam principal investigator and Los Alamos National Laboratory researcher Roger Wiens tells Tech Briefs why the faraway searches from SuperCam are so important to us here on Earth.
Tech Briefs: What are you most excited to learn about through SuperCam?
Roger Wiens: SuperCam will send us a trove of information that we don't currently have from Mars. It represents a new way to look for organic materials on Mars and a new way to study mineralogy, and it will do these studies at an unexplored carbonate-rich site (Jezero crater). On a personal curiosity level, I'm most interested in hearing sounds from Mars on our microphone.
Tech Briefs: What are the differences in capabilities between SuperCam and ChemCam?
Roger Wiens: ChemCam has been exploring Mars since 2012 on the Curiosity rover. Mounted on the rover's mast, it uses laser pulses to give us the chemical composition of rocks and soils up to 7 meters from the rover. The technique is laser-induced breakdown spectroscopy (LIBS), and we've gotten over 700,000 spectra and over 20,000 close-up images from ChemCam.
SuperCam adds remote Raman and passive infrared spectroscopies – two complementary techniques to study mineral compositions. The microphone, which was added during development, will be used to listen to the zapping sounds of the laser plasma on the rock surfaces; those sounds will tell us about the hardness of the rock, without ever driving up to the samples or touching them.
Tech Briefs: What criteria is the A.I. using to find the best areas to sample? What is the A.I. looking for exactly?
Roger Wiens: ChemCam (and soon also SuperCam) uses a package called Autonomous Exploration for Gathering Increased Science (AEGIS), developed by JPL. It picks targets out of a Navcam (wide-field context) image, and it commands the instrument (ChemCam or SuperCam) to perform analyses on the target.
We use AEGIS when the rover arrives at a new site, so we can get compositional data down the same day, without having to wait until humans have seen the new site and picked targets. That kind of human-in-the-loop activity doesn't happen until a day or two later, because we only send commands to the rover once per day or every other day, given the distance to Mars.
So, AEGIS gets us data 1-2 days earlier than we would have it otherwise. AEGIS works most effectively when there is mostly sand around the rover, with only a few rocks in the area. AEGIS picks the rocks as targets, avoiding the sand. It's an obvious choice, and easy for a robot to make. To identify a rock, the software looks for image contrasts that cover an area and shape consistent with a rock.
Other A.I. is used to select a route for long drives. The rover takes images of the terrain around it and picks a route to avoid obstacles. If there are too many obstacles, the rover stops and waits for humans to help.
Tech Briefs: What kind of new A.I. will be a part of the Mars 2020 mission?
Roger Wiens: A third type of AI will be used for the Mars 2020 landing. A new package called Range Trigger determines the best time to deploy the parachute to help the rover land as close as possible to where it should go. Later in the landing sequence, another package called terrain-relative navigation will be used to help the rover avoid the worst obstacles in the area below it. (Learn more about the A.I.. technologies .)
Tech Briefs: Why are these studies, enabled by SuperCam, so important for us to understand?
Roger Wiens: We want to know whether Mars – which once had rivers, lakes, and probably oceans – also had life at that time. Given the long time span between now and the time when Mars was most habitable, it may be difficult to find traces of life. SuperCam and the other instruments on the Mars 2020 rover are supporting the rover's mission to collect drill-core samples that are intended to be returned to Earth by a future mission. Those samples are to be studied in much greater detail in terrestrial laboratories. In the meantime, we want to learn as much as possible about our companion planet, Mars.
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