NASA reveals source of mysterious ‘pulsing’ sound stranded astronauts heard coming from Boeing spacecraft

NASA has explained the source of the mysterious ‘pulsing’ sound heard by the stranded astronauts onboard the Boeing Starliner spaceship.

Back in June, astronauts Barry 'Butch' Wilmore and Sunita Williams left Earth on what was supposed to be eight day trip onboard the maiden voyage of the Boeing aircraft.

However, it's fair to say that things haven't gone quite to plan for Boeing and NASA and, nearly three months later, Wilmore and Williams are still in space, stranded onboard the International Space Station (ISS).

It's been a long few months in space for Barry 'Butch' Wilmore and Sunita Williams (NASA/ Getty Images)

The Starliner is currently scheduled to undock and return to Earth unmanned on 6 September, ready for NASA and Boeing to work out exactly what went wrong on the trip. The spacecraft has reported issues with malfunctioning thrusters and leaking helium, which forced Wilmore and Williams to take up temporary residence on the ISS. However, the problems don't seem to have stopped there.

In the past couple of days, it was revealed that Wilmore had reported hearing 'strange' noises from the Starliner, while it was docked at the ISS.

Which is certainly a little ominous sounding, given the Starliner's rocky track record so far.

Making contact with Houston's Johnson Space Centre to share his concerns, Wilmore said: "I've got a question about Starliner. There's a strange noise coming through the speaker and I didn't know if you can connect into the Starliner... I don't know what's making it."

The astronaut was then able to record the sound and send it to mission control, who confirmed they could hear a 'pulsing' noise and said they would look into the issue.

Thankfully, the noise doesn't seem to be causing too much concern for NASA at the moment, with the space agency now revealing they've been able to locate the source of the noise.

The astronauts ran into problems onboard the Starliner (MIGUEL J. RODRIGUEZ CARRILLO/AFP via Getty Images)

Sharing their findings in a statement, NASA wrote: "The feedback from the speaker was the result of an audio configuration between the space station and the Starliner. The space station audio system is complex, allowing multiple spacecraft and modules to be interconnected, and it is common to experience noise and feedback.

"The speaker feedback Wilmore reported has no technical impact on the crew, Starliner, or station operations."

Meanwhile, Wilmore and Williams have a long wait ahead of them on the ISS, as NASA has confirmed the pair will be returning home via the SpaceX's Crew-9 mission scheduled for February 2025, rather than fly back onboard the Starliner in September.

Talk about a very long eight days in space.