NASA Administrator Bill Nelson said the decision was driven by the agency's commitment to safety, especially after the disasters that beset the space shuttle program.

NASA is investigating a strange noise coming through the speaker on Boeing’s Starliner capsule, which has been beset with technical issues

Space missions are extremely hard. Things going wrong should be expected, so having a sensible plan B is crucial

NASA discovered the cause of a pulsating noise coming from a speaker on the Boeing Starliner spacecraft after astronaut Butch Wilmore reported the sound.

Boeing's Starliner spacecraft landed on Earth Saturday morning, with two test pilots left behind because of NASA's concerns that their return was too risky.

Boeing’s Starliner spaceship has been hampered by a string of errors and delays. WSJ’s Micah Maidenberg explains why Boeing has struggled to launch the Starliner on schedule and what’s next for the aerospace giant’s space program. Photo: NASA/Joel Kowsky

The historic test flight, with fellow astronaut Barry Wilmore, aims to certify Starliner for routine space travel.

Veteran NASA astronauts Sunita Williams and Barry Wilmore, with 500 combined days in space, piloted Boeing’s CST-100 Starliner from Florida, leveraging their extensive experience in spacewalks and ISS command.

This historic mission aims to certify Starliner for routine travel to the International Space Station.

Problems with the capsule’s propulsion system and other related concerns have led to the delay in the astronauts’ return.

Despite the successful landing, two test pilots, Butch Wilmore and Sunita Williams, will remain in space until next year due to NASA’s safety concerns.

Boeing's Starliner spacecraft has left the International Space Station (ISS) and is on its way back to Earth. 

A test run in December was ended early when the spacecraft failed to engage its thrusters on time.

According to NASA, the aerospace company didn't perform a full 'end-to-end' integration test of the software designed to automate maneuvers after the craft is launched into space.

NASA has declined to say whether Starliner will be forced to undergo another test flight before being granted permission to bring human astronauts into space even after a botched mission last year.