Astrobotic has confirmed that the doomed Peregrine Lunar Lander's mission will end on Thursday, January 18 with the spacecraft burning up in the Earth's atmosphere.

On Sunday, January 14, the company said that the spacecraft was 234,000 miles (376,600 km) from Earth and on a path for re-entry.

The question of what to do with the crippled spacecraft has vexed engineers and scientists. The propellant leak ruled out a landing attempt, but the team has managed to extend the life of the lander beyond all expectations. A week ago, mere hours or days were expected from the spacecraft as engineers struggled to understand the issue. A week on from launch, and Peregrine continues to function.

The team has even managed to fire up one of the main engines, saying: "We achieved a 200 millisecond burn and acquired data that indicated Peregrine could have main engine propulsive capability."

The leak has meant the fuel-to-oxidizer ratio is well outside the normal operating range of the engine, making a controlled burn impossible. However, there is enough fuel - the leak has now slowed - to keep the solar arrays pointed at the sun and run Peregrine for a few more weeks. That is, assuming Peregrine's orbit is raised to miss the Earth.

And therein lies the rub. Just because the team could extend the mission does not mean they should. The space community and the US government recommend safely ending the mission now rather than eking a few more days or weeks out of the spacecraft.

"Ultimately," said Astrobotic, "we must balance our own desire to extend Peregrine's life, operate payloads, and learn more about the spacecraft, with the risk that our damaged spacecraft could cause a problem in cislunar space."

The decision is responsible, particularly considering that Peregrine's primary mission - landing on the lunar surface - is a bust. Creating debris in cislunar space or colliding with a satellite in Earth orbit is very much a no-no, and even though the team managed to activate Peregrine's payload, the potential benefit has been deemed not to outweigh the possible risk.

Astrobotic CEO John Thornton paid tribute to the team that had regained control of the spacecraft after Monday's anomaly and, despite the early end, said: "This mission has already taught us so much and has given me great confidence that our next mission to the Moon will achieve a soft landing."

NASA has yet to comment on the impact the failure might have on its next mission to the Moon with Astrobotic - a later 2024 launch and landing of the VIPER rover. The agency's next mission to the Moon under the Commercial Lunar Payload Services (CLPS) program is due to launch in the coming months, using the Intuitive Machines Nova-C lander. ®

https://www.theregister.com//2024/01/15/peregrine_lunar_lander_return/