A First: CubeSat-Style Probes To Accompany InSight Mars Lander

Hundreds of CubeSats have been launched to Earth orbit since 2003. Now, though, two of the small-form-factor craft are set for a deeper space mission. According to Spaceflight Now, The twin CubeSat mission, known as Mars Cube One, will launch on an Atlas 5 rocket in March 2016 with NASA’s InSight lander. The CubeSats will relay status signals from InSight as the landing probe descends through the atmosphere, eliminating potential delays in verifying the success of the mission. ... Each Mars Cube One, or MarCO, CubeSat spacecraft measures 14.4 inches (36.6 centimeters) by 9.5 inches (24.3 centimeters) by 4.6 inches (11.8 centimeters) when closed up for launch, according to the Jet Propulsion Laboratory, which announced details of the mission Friday. The standardized and small CubeSat has made satellite design and launching accessible to schools and others; going to Mars costs a lot more (in this case it's a "$13 million secondary mission"), but it could conceivably put interplanetary probes possible for deep-pocketed universities or corporations.

CUBEsat?

[Ion Berkley]

You know most peoples definition of a Cubesat is ....a cube shaped satellite, ie all 3 axises have the same length.....now admittedly there are 2U and 3U variants i.e. 2 and 3 stacked cubes.

This is a micro-satellite, not a cubesat

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[Coren22]

Holy shit was what happened when Jesus visited the privys.

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[Brett Buck]

That's a pretty minor distinction. I was an industry advisor for what might have been the first 3-high cubesat. The only important restriction is that it fit in the ejection canister.

The basic single 4.5" cubical satellite is *very limited* in capability due to lack of any viable attitude control and very low power available. It's tough to do anything useful even in low Earth orbit. That would be crippling for an interplanetary mission.

I expect someone may have wo

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[necro81]

I expect someone may have worked out the numbers, but for a Mars relay you have more-or-less no attitude control and need a fair bit of power for at least several hours

The article mentions that the MarCO sats will have cold-gas thrusters for course correction and attitude adjustment. There are also a set of three reaction wheels for fine attitude adjustment. I expect the attitude adjustment is for optimal solar panel alignment during the cruise, then for radio alignment during the InSight landing.

Re:CUBEsat?

[radarskiy]

The *actual* definition of a CubeSat is a satellite built in multiples of a 1 L unit that is compatible with an OPAL microsatellite used as a launcher. MarCO meets the specifications for a 6U CubeSat.

MarCO itself is not large enough to meet the specifications of a microsatellite.