NASA's Lunar Trailblazer is Launching to the Moon

A new mission to study the Moon is scheduled to launch this week.

NASA's Lunar Trailblazer mission is led by Caltech's Bethany Ehlmann, professor of planetary science and the Allen V. C. Davis and Lenabelle Davis Leadership Chair and director of the Keck Institute for Space Studies, and the mission is operated by IPAC at Caltech. The Lunar Trailblazer small satellite, or smallsat, will orbit the Moon to understand the nature of water on the Moon's surface, providing maps to guide future robotic and human explorers. Prior missions have seen hints of ice and other forms of water that could be used in a variety of ways, from purifying it for human use, to processing it for fuel and breathable oxygen for future human Moon landings.

"Lunar Trailblazer pushes frontiers in a number of ways as a class of low-cost, higher-risk NASA mission that paves the way understanding ice on the Moon, the water cycle on airless bodies, and resources for future explorers, all while being university based and training the next generation of explorers," says Ehlmann.

The debate about why the Moon has water has focused on two possibilities: One scenario involves comets and "wet asteroids" crashing into the Moon, while the other entails ancient volcanic eruptions disgorging water vapor from the Moon's interior and depositing frost on its surface. Lunar Trailblazer's findings will shed light on which hypothesis is more likely and, importantly, provide maps of how much water is where on the surface. Tiny amounts are seen on the sunlit parts of the Moon now, but theory and some datasets suggest that large deposits of ice might be in permanently shadowed regions located at the Moon's poles.

The mission makes its measurements with two science instruments: the Lunar Thermal Mapper (LTM), built at the University of Oxford and funded by the UK Space Agency, and the High-resolution Volatiles and Minerals Moon Mapper (HVM3), built at NASA's Jet Propulsion Laboratory (JPL). Caltech manages JPL for NASA.

The launch period opens February 26, and the mission then takes a low-energy trajectory that uses Earth-Moon-Sun gravity assists to insert into orbit around the Moon four to seven months later. When it arrives, it will use HVM3 to map the wavelengths of reflected sunlight from the different forms of water over the shadowy craters and the lunar landscape. LTM will scan those mapped regions at the same time to map the temperature of the surface. By measuring the same locations at different times of day, Lunar Trailblazer will determine if the amount of water changes on this airless body.

A feature of the mission is that spacecraft operations are based at a university rather than in aerospace industry or a NASA center. Caltech's IPAC will operate Lunar Trailblazer from campus, leveraging decades of experience operating space telescope science instruments and its data processing. Undergraduate students from Caltech and Pasadena City College also work on Lunar Trailblazer's mission ground software and commanding under the guidance of IPAC technical staff, providing training internships working on a space mission.

"Lunar Trailblazer offers an opportunity to leverage IPAC experience in new ways to enable efficient campus-based mission operations," says George Helou, research professor of physics and executive director of IPAC. "Innovative approaches to operations, including student contributions, are necessary to realize the scientific promise of smallsats within their limited budgets."

Managed by JPL, Lunar Trailblazer was selected as a NASA SIMPLEx (Small Innovative Missions for Planetary Exploration) mission in 2019. It is part of NASA's Lunar Discovery and Exploration Program (LDEP), which is managed by NASA's Planetary Missions Program Office (PMPO) at Marshall Space Flight Center in Huntsville, Alabama, for the agency's Science Mission Directorate (SMD) in Washington. The spacecraft will launch as a secondary commercial payload, sharing the ride to space on a SpaceX Falcon 9 rocket with the second Intuitive Machines robotic lunar lander mission, called IM-2.