Mars Cube One
Mars Cube One (MarCO) was a Mars flyby mission launched on 2018-May-5 alongside NASA's InSight Mars lander mission. It consisted of two CubeSats, MarCO-A and MarCO-B, that provided a real-time communications link to Earth for InSight during its entry, descent, and landing (EDL) on 2018-Nov-26. These were the first CubeSats to operate beyond Earth orbit, and aside from telecommunications they also tested CubeSats' endurance in deep space. On 2019-Feb-5, NASA reported that both the CubeSats had gone silent by 2019-Jan-5, and are unlikely to be heard from again.
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