Boeing’s Starliner has been dogged with problems for months, leading to two astronauts getting stranded in space for months longer than planned.
But the latest issue has people scratching their heads, with a strange ‘sonar-like’ noise recorded coming from the spacecraft, which is currently docked to the International Space Station (ISS) before it is due to fly home without crew.
The repetitive pulsing stumped NASA astronaut Butch Wilmore, who told Mission Control at Johnson Space Center in Houston he did not know what was causing it.
As first reported by Ars Technica, he radioed down: ‘I’ve got a question about Starliner.
‘There’s a strange noise coming through the speaker … I don’t know what’s making it.
‘I’ll do it one more time, and I’ll let y’all scratch your heads and see if you can figure out what’s going on.’
Mission Control agreed it was ‘kind of like a pulsating noise, almost like a sonar ping’ but could not say what had caused it, saying they would investigate further.
Mr Wilmore had been due to fly back to Earth along with fellow astronaut Sunita Williams, but helium leaks and thrust failures during their journey to the ISS meant the capsule was not deemed reliable enough.
They are currently still in space and are due to get a lift back with Space X’s Dragon capsule in February.
After reports of the weird noise were circulated, retired astronaut Chris Hadfield, a former commander of the ISS, shared audio of the sound and said: ‘There are several noises I’d prefer not to hear inside my spaceship, including this one that @Boeing Starliner is now making.’
Although the sound was compared to the sonar pings of a submarine, it could not actually be sonar coming from space as the technique uses sound waves, which cannot occur in space as it is a vacuum.
The next logical answer (ahem), is space ghosts, which were the go-to solution for many who shared the sounds online.
Joking aside, there is more than likely a technical explanation, such as when a strange knocking noise was noted on China’s first crewed spaceflight on 2003 which was due to a difference in pressure between the craft’s inner and outer walls.
One explanation could be some form of interference with the speaker, potentially from other systems on the ISS.
Whatever the cause, it makes for more headlines about the beset Starliner which Boeing could do without.
It comes after Nasa announced they had to cut two female astronauts from the next crew due to fly to the ISS, to make room on the return trip for Suni Williams and Butch Wimore to come back home.
Nasa’s Nick Hague and Russian Aleksandr Gorbunov will launch in September aboard a SpaceX rocket for the orbiting laboratory, but Zena Cardman and Stephanie Wilson were bumped from it.
Nasa said they could fly on future missions.
The space agency said it took into account spaceflight experience and other factors in making the decision.
Nasa turned to private businesses a decade ago, wanting two competing US companies ferrying astronauts in the post-shuttle era instead of having to rely on Russia.
Ms Williams and Mr Wilmore were Boeing’s first crew, arriving at the space station in June for what was supposed to be a week-long stay.
Their Starliner capsule is due to return empty as early as next Friday, aiming for a touchdown in the New Mexico desert.
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