NASA has completed the mission of the cube satellite, which was supposed to enter lunar orbit but could not due to problems with its propulsion system. NASA’s Jet Propulsion Laboratory announced on May 12 that the Lunar Flashlight mission has ended, five months after its launch. The spacecraft could not enter its planned polar orbit around the Moon, as the propulsion system could not produce the necessary thrust.

Engineers spent several months fixing the issue, which was discovered shortly after launch in December 2022. They suspected that some debris was clogging the fuel lines and reducing the amount of fuel reaching the engines. On May 5, NASA said they were making a final effort to clear the jam by pushing fuel pump pressure “well beyond” operating limits as the valves opened and closed. Tested on one of the spacecraft’s four engines, the technique had some success, “producing some increased thrust levels inconsistently.”

However, these efforts were not enough to keep the spacecraft close to the moon and forced JPL to finish the mission. At the time, mission planners had refused to place the spacecraft in a near-straight halo orbit around the moon, but hoped to be able to place it in a distant low-Earth orbit that would allow for monthly flights to the moon.

It is unknown how the debris reached the power plant. In a recent interview, Daniel Cavender, NASA’s cube satellite propulsion project manager and director of Rubicon Space Systems, division of Plasma Processes LLC, which is currently commercializing the propulsion system, pointed out the limitations imposed by the cube satellite 6U. The design limited the engineers’ ability to fit filters into the system.

“We couldn’t put filters everywhere because of the size limitation. As a result, we relied heavily on precision cleaning, inspections and contamination control. But at one point there was a glitch in the process,” he said. He noted that data from Cubesat are consistent with ground-based testing of engines with debris in their fuel lines.

Moonlight was the first spacecraft to go beyond Earth orbit using a non-toxic, “green” fuel called Advanced Spacecraft Energetic Non-Toxic, or ASCENT, developed at the Air Force Research Laboratory. Cavender described it as “an important test in space”, noting that the engines performed well until the debris problem deprived them of fuel.

NASA highlighted other technologies that the Lunar Flashlight has successfully tested. These included a new onboard computer called the Sphinx, capable of operating at low power levels and surviving in the radiation environment of deep space, and an upgraded radio called Iris.

“Technology demonstrations are inherently higher risk and higher reward, so testing and education are important to NASA,” said Christopher Baker, small spacecraft technology program manager at NASA’s Space Technology Mission Directorate. Said. end of mission “Moonlight has been very successful in testing new systems that have never flown into space before.”

The lunar lantern also had a science mission that used a laser reflectometer to look for water ice in permanently shadowed craters at the moon’s south pole. While the spacecraft will not be able to collect any scientific data, it has tested the craft and confirmed that it works as expected.

“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, principal investigator at the mission’s Goddard Space Flight Center. expression. However, he added that the mission “collects a lot of in-flight vehicle performance data” that can be used to design similar vehicles for future missions.

Moonlight first appeared on Artemis 1, the first launch of a Space Launch System rocket along with 12 other cubic moons. But changes to the power plant’s design meant that the spacecraft had to integrate it into the SLS in the fall of 2021. Instead, NASA used it as an auxiliary payload during the Falcon 9 launch of Japanese company ispace’s HAKUTO-R M1 lander, which launched less than a month after Artemis 1.

Several of the 10 cube satellites launched on Artemis 1 also experienced technical problems that prevented them from completing their mission. At the May 1 workshop, Craig Hardgrove, principal investigator of the LunaH-Map cube satellite, said his team is still working on resolving an issue with the electric propulsion system. At the time, he said, if they weren’t able to free a stuck valve in the system by the end of May, they would likely shut it down. JPL said the Lunar Flashlight will pass near Earth on May 17 at an altitude of 65,000 kilometers and then travel into deep space. As the spacecraft’s other systems continue to operate despite engine problems, “NASA is considering options for the spacecraft’s future.”