November 27, 2018 – Two CubeSats had a front row seat when NASA’s newest lander successfully touched down on the Martian surface on Monday, November 26. The twin spacecraft, called Mars Cube One (MarCO), made history by successfully relaying real-time data back to Earth as InSight descended through the atmosphere and landed near Mars’ equator on a flat, smooth plain called Elysium Planitia.
The MarCO demonstration provided two identical satellites for redundancy — MarCO-A and MarCO-B. Nicknamed “EVE” and “WALL-E” after the stars of the 2008 Pixar film, the CubeSats used experimental radios and antennas, providing an alternate way for engineers to monitor the landing. MarCO provided information to InSight’s landing team on Earth in only 8 minutes – the time it takes for radio signals to travel from Mars to our home planet.
“WALL-E and EVE performed just as we expected them to,” said MarCO chief engineer Andy Klesh of NASA’s Jet Propulsion Laboratory in Pasadena, California, which built the CubeSats. “They were an excellent test of how CubeSats can serve as ‘tag-alongs’ on future missions, giving engineers up-to-the-minute feedback during a landing.”
CubeSats are a class of spacecraft based on a standardized small size. Simpler, smaller and more affordable than traditional satellites, they’ve made space more accessible to private companies and universities. The basic CubeSat unit is a box roughly 4 inches (10 centimeters) square. Larger CubeSats are multiples of that unit. MarCO’s design is a six-unit CubeSat – about the size of a briefcase — with a stowed size of about 14.4 inches (36.6 centimeters) by 9.5 inches (24.3 centimeters) by 4.6 inches (11.8 centimeters).
The technology demonstration was developed to see whether CubeSats could survive a trip to deep space. MarCO’s radios, high-gain antennas, attitude control and propulsion systems were all included to prove new technologies. By completing the mission, MarCO has demonstrated how CubeSat technology can be used beyond low Earth orbit to further explore the solar system.
CubeSats are distinctively modular, utilizing off-the-shelf technologies rather than custom-designing every part of the spacecraft. MarCO’s solar panels, cameras, avionics, propulsion systems and attitude-control systems were all provided by commercial contractors, including two Colorado companies.
Blue Canyon Technologies (BCT) of Boulder provided the attitude control system, giving MarCO the precision pointing required to get to Mars. BCT’s XACT (fleXible Attitude Control Technology) module utilizes a nano star tracker, precision reaction wheels, and all associated electronics and software. Already designed to support virtually any low-earth-orbit mission, the XACT software was augmented for MarCO to support deep-space navigation, including thruster control algorithms for momentum control and precision trajectory corrections throughout the journey to Mars.
MMA Design of Louisville, Colorado provided HaWK Solar Arrays for MarCO. Both satellites were programmed to unfold their solar panels soon after launch in order to provide critical power for their deep space mission.
The MarCO mission didn’t carry science instruments, but that didn’t stop the team from testing whether future CubeSats could perform useful science at Mars. As MarCO-A flew by the planet, it conducted some impromptu radio science, transmitting signals through the edge of Mars’ atmosphere. Interference from the Martian atmosphere changes the signal when received on Earth, allowing scientists to determine how much atmosphere is present and, to some degree, what it’s made of.
As a bonus, some consumer-grade cameras aboard MarCO provided “drive-by” images as the CubeSats sailed past Mars. MarCO-B was programmed to turn so that it could image the planet in a sequence of shots as it approached Mars (before launch, MarCO-A’s cameras were found to be either non-functioning or too blurry to use).
After InSight’s landing, MarCO-B turned backward to take a farewell shot of the Red Planet. It also attempted to snap some photos of Mars’ moons, Phobos and Deimos.
“WALL-E sent some great postcards from Mars!” said Cody Colley of JPL, MarCO’s mission manager, who led the work to program each CubeSat to take images. “It’s been exciting to see the view from almost 1,000 miles (1,600 kilometers) above the surface.”
The mission objective of the two small MarCOs was completed after their Martian flyby.
“That’s one giant leap for our intrepid, briefcase-sized robotic explorers,” said Joel Krajewski, MarCO project manager at JPL. “I think CubeSats have a big future beyond Earth’s orbit, and the MarCO team is happy to trailblaze the way.”
The MarCO team will spend the next couple of weeks collecting additional data on each CubeSat. Of interest will be how much fuel is left in each CubeSat and detailed analyses of how their relay capability performed.
JPL, a division of the California Institute of Technology in Pasadena, manages MarCO and InSight for NASA’s Science Mission Directorate in Washington. Technology suppliers for MarCO include: Blue Canyon Technologies of Boulder, Colorado, for the attitude-control system; VACCO Industries of South El Monte, California, for the propulsion system; AstroDev of Ann Arbor, Michigan, for electronics; MMA Design LLC, also of Boulder, for solar arrays; and Tyvak Nano-Satellite Systems Inc., a Terran Orbital Company in San Luis Obispo, California, for the CubeSat dispenser system.