NASA’s Mars 2020 rover to be equipped with 23 ‘eyes’
One of the key instruments that has accompanied every rover since Pathfinder became the first rover to land on the surface of Mars in 1997 are imagers – cameras. NASA’s newest rover continues this trend. In addition, it continues the trend of increased visible acuity that accompanies the increased instrument performance and improved technology.
Pathfinder launched with five cameras – two on the rover’s mast, and three on the Sojourner lander itself. When the two rovers of the Mars Exploration Rover (MER) mission – Spirit and Opportunity – landed on Mars, they each had 10 cameras. The Mars Science Laboratory (MSL) Curiosity rover went equipped with 17 cameras. By comparison, the Mars 2020 rover will launch equipped with 23 cameras – many of which are high definition, high resolution, and in color.
“Camera technology keeps improving,” Justin Maki of JPL, Mars 2020’s imaging scientist and deputy principal investigator of the Mastcam-Z instrument said via a press release. “Each successive mission is able to utilize these improvements, with better performance and lower cost.”
Many of those 23 cameras are upgrades of the same types cameras on Curiosity, but others are brand new.
The Enhanced Engineering Cameras are primarily improvements to the ones on Curiosity and consist of two sets each of front and rear Hazcams and Navcams as well as the new CacheCam.
The new and improved cameras should also improve overall driving capabilities by providing clearer, sweeping wide-angle panorama images needed for autonomous navigation through the Martian terrain utilizing stereoscopic (3-D) placement.
Unlike on Curiosity, many of Mars 2020’s imaging instruments are color capable and can see details much farther. The Navcams can ‘see’ a golf ball from 82 feet (25 meters) away and have a “drive blind” mode to aid in autonomous driving as well as hazard and obstacle avoidance.
“Routinely using 3-D images at high resolution could pay off in a big way,” Jim Bell of Arizona State University, Tempe, principal investigator for 2020’s Mastcam-Z said. “They’re useful for both long-range and near-field science targets.”
The new cameras are improved from Curiosity’s 1-megapixel resolution to 20 megapixels, with 5120 × 3840 pixel resolution that no longer requires that many smaller images be stitched together.
“Our previous Navcams would snap multiple pictures and stitch them together,” said Colin McKinney of JPL, product delivery manager for the new engineering cameras. “With the wider field of view, we get the same perspective in one shot.”
The new CacheCam that is part of the Enhanced Engineering Cameras will provide microscopic, top-down views of the rock samples that are collected inside of the vials prior to being sealed as part of the sample-return caching system.
The Science Cameras consist of seven imagers. The first, Mastcam-Z (a pair), is similar to Curiosity’s Mastcam that provides 3-D stereoscopic images, but Mastcam-Z also has color imaging and video as well as a 3:1 zoom lens. The other improved imager amongst the Science Cameras is the SuperCam (Remote Micro-Imager [RMI]), which is similar to Curiosity’s ChemCam. SuperCam will be able to utilize a laser to zap mineral targets smaller than 1 millimeter from more than 20 feet (7 meters) away. Like ChemCam, the SuperCam will use spectrometers to analyze the light signatures from the minerals to determine their contents.
The four other science cameras include PIXL, SHERLOC, WATSON, and SkyCam. PIXL is a micro-context camera using X-ray fluorescence. SHERLOC’s macro imager is used in coordination with spectrometers and lasers to get extreme close-up images to distinguish textures that may assist researchers in understanding how the minerals formed. WATSON is an imaging instrument nearly identical to the functionality of the MAHLI instrument on Curiosity, but better.
WATSON is located on a turret mounted on the robotic arm of the rover and can be positioned to not only look at the various samples on the surface of Mars but also to do inspections of other instruments, including of Mars 2020 itself. This, in partnership with Navcam, should provide a good way to monitor the health of Mars 2020, as well as being able to take some fantastic selfies.
Lastly amongst the new Science Cameras is the SkyCam. SkyCam, much like its name implies, is a sky-facing camera that is part of a suite of weather instruments that will study the clouds and atmosphere on Mars.
The seven Descent Imaging Cameras will provide the spacecraft with four views including look-up cameras from the descent stage which will record images and video of a parachute deploying and inflating on another planet for the first time.
Along with the look-up cameras, the descent stage will have look-down cameras to view the rover from above, while the rover will have look-up cameras to see how the descent stage is operating as it is lowered from the sky crane. The rover will also have a downward looking camera to view the ground as it approaches.
The Descent Imaging Cameras should provide the first-ever front-row seat to a Mars landing.
In addition to the increased performance capability, the Mars 2020’s cameras are also incredibly light, weighing less than one pound (<425 grams). The imaging systems have also gotten a lot smarter, with the capability of image compression being done directly in the cameras rather than on the onboard computer.
The landing of the Mars 2020 rover won’t be without difficulty, however. More data means more data to transfer which will be a challenge even with current capabilities.
“The limiting factor in most imaging systems is the telecommunications link,” Maki said. “Cameras are capable of acquiring much more data than can be sent back to Earth.”
The new data will need to be transferred from the surface to orbiting satellites to be relayed to the Deep Space Network (DSN) on Earth, something that was pioneered with the MER Spirit and Opportunity rovers using Mars Odyssey as a relay.
“We were expecting to do that mission on just tens of megabits each Mars day, or sol,” said Bell. “When we got that first Odyssey overflight, and we had about 100 megabits per sol, we realized it was a whole new ballgame.”
The number of satellites capable of doing that data transfer won’t be increasing, while the number of spacecraft on the surface will. By the time Mars 2020 lands, the InSight lander should also be on the surface needing to transfer data back to Earth, as well.
This could tax an aging and already busy network of spacecraft. Currently, the only satellites capable of transferring data from the surface and relaying it to the DSN are Mars Reconnaissance Orbiter (MRO), MAVEN, and the European Space Agency’s (ESA) Trace Gas Orbiter, but NASA seems confident that the trio of satellites will be able to support the new rover in its first two years on the Martian surface.
A native of the Greater Los Angeles area, Ocean McIntyre's writing is focused primarily on science (STEM and STEAM) education and public outreach. McIntyre is a NASA/JPL Solar System Ambassador as well as holding memberships with The Planetary Society, Los Angeles Astronomical Society, and is a founding member of SafePlaceForSpace.org. McIntyre is currently studying astrophysics and planetary science with additional interests in astrobiology, cosmology and directed energy propulsion technology. With SpaceFlight Insider seeking to expand the amount of science articles it produces, McIntyre was a welcomed addition to our growing team.