Astrobotic’s Peregrine lunar lander failed to reach the moon due to a malfunctioning pressure control valve (PCV2), which caused a propellant leak after launch. The leak, attributed to “vibration-induced relaxation” in the valve’s threaded components, led to the spacecraft’s oxidizer tank rupturing. The lander flew through cislunar space for 10 days before reentering over the South Pacific. Astrobotic is now redesigning the valve and propulsion system for its larger Griffin lander.