Mars Cube One (MarCO)

Mars Cube One (MarCO) was a pair of small, lightweight spacecraft called CubeSats launched in 2018 to support NASA’s Mars InSight lander. Their main role was to relay real-time data during InSight's landing, providing a new way to communicate directly with Earth without relying solely on larger orbiters. Despite their small size, MarCO successfully sent and received signals, demonstrating that inexpensive, compact satellites can assist in complex space missions. Although they lost contact shortly after landing, MarCO proved the value of small satellites for rapid, flexible space communication and exploration support.