While CubeSat couldn’t reach the Moon’s south pole to help find ice, it did achieve several technological goals that would advance future missions for the benefit of humanity. NASA terminated the Moon Flashlight mission, which it launched in 2022, due to insufficient propulsion from its small propulsion facility. Although the goal of detecting ice on the lunar surface was not achieved, the mission received valuable data from new technologies, several components exceeded expectations. Now the satellite is returning to Earth, its future is being considered by NASA.

NASA’s Lunar Lantern was launched on December 11, 2022, to demonstrate several new technologies with the ultimate goal of searching for surface ice in the permanently shadowed craters of the Moon’s South Pole. Since then, the briefcase-sized satellite’s miniature propulsion system – the first of its kind ever launched – has failed to generate enough thrust to reach lunar orbit, despite months of efforts by the operations team. NASA announced the end of the mission, as CubeSat was unable to complete maneuvers that would remain in the Earth-Moon system.

NASA relies on technology demonstrations to fill knowledge gaps and test new technologies. Such demonstrations included the Lunar Flashlight propulsion system and ecological fuel used for the first time outside of Earth orbit. The newly developed propulsion components exceeded expected performance, although the propulsion system was unable to provide the desired thrust, possibly due to deposits in the drive fuel lines.

Also exceeding expectations was the never-before flown Lunar Flashlight Sphinx onboard computer – a low-power computer developed by NASA’s Jet Propulsion Laboratory in Southern California to withstand the radiation of deep space – and the spacecraft’s upgraded Iris radio. With its new precision navigation capability, the radio could be used by future small spacecraft to rendezvous and land on solar system bodies.

“Technology demonstration is inherently higher risk and higher reward, so testing and education are important to NASA,” said Christopher Baker, small spacecraft technologies program manager at the Space Technology Mission Office at NASA Headquarters in Washington. “Moonlight has been very successful in testing new systems that have never flown into space before. These systems and lessons learned from Lunar Flashlight will be used for future missions.”

The mission’s miniature four-laser reflectometer, a never-before-flyed science instrument, was also successfully tested, reassuring the mission’s science team that the laser could detect ice if found on the moon’s surface.

“It’s disappointing to the science team and the entire Lunar Flashlight team that we won’t be able to use our laser reflectometer to measure on the Moon,” said Barbara Cohen, the mission’s principal investigator at NASA’s Goddard Space Flight Center. in Greenbelt, Maryland. “But like any other system, we’ve collected a lot of data about the instrument’s flight performance, which will be incredibly valuable for future iterations of this technique.”

Power plant performance issues

Despite the mission’s technological achievements, the tiny Lunar Flashlight thruster struggled to provide enough thrust to send the CubeSat into a planned, nearly flat halo orbit that would enable weekly flights of the Moon’s south pole.

The team suspects debris clog fuel lines, causing reduced and erratic thrust. The miniature engine likely contained an additive-generated fuel delivery system that produced debris such as metal dust or sawdust and blocked the flow of fuel to the engines, limiting their performance. Although the team found a creative way to use just a single engine to maneuver the spacecraft, the Lunar Lighthouse needed more stable thrust to reach its intended orbit.

The task force calculated a new trajectory that could be reached using the spacecraft’s small potential residual thrust. The plan required the CubeSat to orbit the Earth instead of the Moon with monthly flights of the Moon’s South Pole. The spacecraft would fly closer to the surface, although that would mean fewer flights.

As the mission expired to reach the required orbit, the task force sought to remove debris from the fuel lines by increasing the fuel pressure well above the design power of the propulsion system. Despite limited success, the required trajectory correction maneuvers were not completed in time.