Deep Space Cubesats with MarCO
NASA’s twin Mars Cube One (MarCO) cubesats successfully completed their demonstration mission of relaying telemetry from the Mars InSight lander during InSight’s descent into the Martian atmosphere on November 26, 2018. This is a major milestone for cubesats because it validates that they can survive deep space and provide unique capabilities to future deep space missions.
The two MarCO cubesats are independent spacecraft the size of a briefcase that survived deep space for seven months as they followed Insight’s travel towards Mars. Their primary mission was to be a dedicated platform for observing the entire Insight landing, by relaying radio signal immediately to NASA controllers on Earth. By immediately relaying Insight’s signal, Earth’s wait for the landing observation signal was closer to the minimum signal travel time between Mars and Earth. Without MarCO, controllers would have had to rely on NASA’s other orbiters to relay Insight’s signals, however, they were not positioned to observe the entire descent and landing while beaming the signals back to Earth.
Mission planners can use this success for structuring the use of cubesats for future deep space missions, especially for those that will visit near-Earth objects (NEO). A hypothetical asteroid prospecting mission could include one or two cubesats flying to multiple different NEOs in an attempt to survey each one for volatiles, composition, size, and other physical features. This would enable a follow up mission to target only the best candidate object.
For now though, both MarCO cubesats are well past Mars on their heliocentric orbits. Their performance will continue to be evaluated for additional insights until they run out of fuel.