NASA’s next mission to Mars will include a stationary lander and two CubeSats. This will be the first time that CubeSats have flown in deep space and demonstrated their feasibility to be used to relay communications from the lander to Earth. If successful, the technology will provide NASA with the ability to quickly transmit status information about a main spacecraft after it lands on Mars.
NASA’s Jet Propulsion Laboratory in Pasadena, California will construct the twin communications-relay CubeSats, which will be called Mars Cube One (MarCO). CubeSats are a class of spacecraft based on a standardized small size and modular use of off-the-shelf technologies. University students have made them and dozens have been launched into Earth orbit using extra payload mass available on launches of larger spacecraft.
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).
MarCO will launch in March 2016 from Vandenberg Air Force Base in California on the same United Launch Alliance Atlas V rocket as NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) lander. InSight will provide NASA with data on the interior structure of the Red Planet. MarCO will fly by Mars while Insight is landing in September 2016. In other words, it will fly independently to Mars.
During InSight’s entry, descent and landing operations on September 28, 2016, the lander will transmit information in the UHF radio band to NASA’s Mars Reconnaissance Orbiter flying overhead. The Orbiter will forward the lander’s status information to Earth using a radio frequency in the X band, but cannot simultaneously receive information over one band while transmitting on another. The orbiter could receive confirmation of a successful land more than an hour before it’s relayed to Earth.
MarCO will provide both UFH (receive only) and X-band (receive and transmit) functions capable of immediately relaying information received over UHF.
If the MarCO demonstration mission succeeds, it could allow for a “bring-your-own” communications relay option for use by future Mars missions in the critical few minutes between Martian atmospheric entry and touchdown.