NASA blames blocked propellant lines for lunar cubesat’s doom

Ongoing problems

These problems left the craft unable to perform the maneuvers needed to go into orbit around the moon and JPL was forced to end the Lunar Flashlight mission on May 12, a mere five months after its launch.

Space News reported that NASA engineers did attempt a technique to perform trajectory correction maneuvers with a single thruster that initially worked. However, a ninth attempt of the maneuver saw thrust drop to zero. 

“Thruster four was basically considered dead then, and we knew a lunar orbit was no longer possible,” Cheek said, according to Space News.

The engineers then tried a maneuver to enable a series of lunar flybys using thruster three but that proved a failure too.

Further investigation by the agency revealed that the source of the debris in the thrusters was likely sintered titanium particles that may have dislodged themselves from the interior of propellant lines due to the vibrations that occurred before and during launch.

Still a success

On Monday, Chris Baker, program executive for small spacecraft technology programs in NASA’s Space Technology Mission Directorate, said at a NASA town hall meeting that the agency still deemed the mission a success.

“Our Lunar Flashlight spacecraft unfortunately did not make it to the moon, but we learned a lot from that mission,” said Baker, according to Space News.

This is a feeling the executive had shared previously in a NASA statement.

"Technology demonstrations are, by their nature, higher risk and high reward, and they're essential for NASA to test and learn," Baker explained.

"Lunar Flashlight was highly successful from the standpoint of being a testbed for new systems that had never flown in space before. Those systems, and the lessons Lunar Flashlight taught us, will be used for future missions."

Indeed, despite not ever reaching orbit, Lunar Flashlight was able to undertake demonstrations of the laser reflectometer science instrument as well as a never-before-flown Sphinx flight computer – a low-power computer developed by JPL in Southern California to withstand the radiation of deep space – and the spacecraft’s upgraded Iris radio.