- By Jonathan Amos
- Science reporter
The American company, which had hoped to land on the moon, will bring its mission home in the next few hours.
Astrobotic says its Peregrine spacecraft will re-enter Earth's atmosphere and burn up.
The lander suffered a major propellant leak shortly after it was launched on a Vulcan rocket from Florida last week.
Even if the engineers were able to stabilize the situation, the loss of the oxidizer meant that a safe touch-down on the lunar surface would never be attempted.
Astrobotic, based in Pittsburgh, has decided to dispose of the craft, which wander aimlessly through space and pose a risk of collision.
“Astrobotics has positioned the Peregrine spacecraft for a safe, controlled re-entry to Earth in a remote location in the South Pacific. The team continues to monitor our re-entry analysis. [the US space agency, Nasa],” the company said in its latest mission update.
“We expect re-entry to occur at approximately 16:00 on Thursday 18 January EST (21:00 GMT).”
Astrobotics' goal was to deliver five NASA instruments to the lunar surface to study the local environment ahead of the astronauts' return later this decade.
If the Peregrine craft manages to land successfully, it would be the first American mission to do so in half a century and the first private attempt to achieve the feat.
The United States, the Soviet Union, China, and India are the only government agencies that have controlled lunar landings to date.
But Astrobotic can console himself with what he managed to achieve from a difficult situation.
Engineers figured out what went wrong with Peregrine and managed to squeeze life out of the lander beyond what initially seemed possible.
“Space exploration is a learning game, and especially at this stage we shouldn't look at it as a failure, we should look at it as an incredible engineering success,” said Sian Cleaver, industrial manager of Airbus' Orion European service block. The BBC's Today programme.
“At one point the mission seemed doomed, but a team of engineers and scientists came together to solve the problem, restore some of the spacecraft's capabilities, and eventually return it to Earth,” he said. “I think it's actually very interesting.”
“There are a lot of things we can take from this, but ultimately space travel is hard, and that's what we see here.”
The fault was traced to propellant leaking from a corroded oxidizer tank. This created a thrust, turning the craft and preventing it from continuously pointing its solar panels towards the sun – crucial for maintaining a power supply.
The Astropodic team used thrusters on the peregrine to restore stable pointing, but this made even more use of rapidly depleting oxygen.
Nevertheless, the payloads on board were activated and proved their spaceworthiness, and some were able to collect data such as the nature of the radiation environment between Earth and the Moon.
The tool was reported to perform well in check-out tests. The technology will then have the chance to fly again on lunar missions.
Astrobotic is the first of three U.S. companies to send a lander to the moon this year under a new private-public partnership with NASA.
The agency buys transportation services from the Pittsburgh company and two other business ventures — Intuitive Machines and Firefly. Together, the three planned six missions to the lunar surface by 2024.
Astrobotic should get a second mission later in the year when it tries to land a NASA rover called Viper. Houston-based Intuitive Machines' first venture will launch next month. Its Nova-C craft will aim for the Moon's south pole.
Before that, the Japanese space agency will try to safely land an impact crater near the equator called Shioli. The event is scheduled for Friday at 15:20 GMT.