Boeing's problem-plagued Starliner spacecraft landed in New Mexico early Saturday after undocking from the International Space Station, leaving two American astronauts behind.
The capsule "Calypso," which was supposed to return U.S. astronauts Butch Wilmore and Suni Williams to Earth back in June, took about six hours to successfully land, empty, a minute after midnight at White Sands Space Harbor in New Mexico, NASA reported.
Due to problems with Starliner's propulsion system Wilmore and Williams will now have to stay at the space station through the rest of the year and won't be able to return to Earth until February — aboard SpaceX's Dragon spacecraft.
The Starliner would have been manned by the astronauts in a typical undocking and flight back home Friday. This time it was empty.
"We have your backs, and you've got this," Williams told mission controllers at NASA's Johnson Space Center in Houston before the Starliner headed home.
"Bring her back to Earth. Good luck," she added.
The Calypso's stay at the ISS turned out to be nearly three months longer than NASA had planned. It was initially only expected to be away for about nine days.
But as Starliner approached the space station with Wilmore and Williams aboard June 6, NASA and Boeing identified helium leaks and issues with the spacecraft's reaction control thrusters. Officials subsequently delayed the spacecraft's return several times as engineers collected more information about the propulsion system.
NASA officials ultimately decided in late August that the agency would send Starliner back without the astronauts in order to first "further understand the root causes" of the spacecraft's problems.
As part of its Commercial Crew Program NASA officials had hoped to have two companies — Boeing and SpaceX — flying alternating missions to the space station.
But Starliner's problems have thrown a wrench into the works. The $1.5 billion in losses in the program already could threaten Boeing future involvement with the plan.
NASA put a good spin on the Starliner project.
"I am extremely proud of the work our collective team put into this entire flight test, and we are pleased to see Starliner's safe return," said Ken Bowersox, associate administrator, Space Operations Mission Directorate at NASA Headquarters in Washington.
"Even though it was necessary to return the spacecraft uncrewed, NASA and Boeing learned an incredible amount about Starliner in the most extreme environment possible," he added.
