Engineers examining the MSoLo (Mass Spectrometer Observing Lunar Operations) instrument for VIPER (Volatiles Investigating Polar Exploration Rover) after it arrives at NASAs Johnson Space Center in Houston, USA on 27 February 2023. MSoLo is a modified commercial off-the-shelf mass spectrometer built to withstand the harsh lunar environment. It will help the VIPER mission team analyse the chemical makeup of the lunar soil and study water on the surface of the Moon. MSolo, as part of VIPER, will launch on a SpaceX Falcon Heavy rocket, through NASAs?¯Commercial Lunar Payload Services (CLPS) initiative. VIPER will land at Moons South Pole aboard Astrobotics Griffin lander in late 2024 for a 100-day mission as part of NASAs?¯Artemis?¯missions.