Last week, Nasa and the Russian space agency scrambled to fix a leak in the floating laboratory that was causing air to slowly rush out of the space station. The crew on board eventually plugged up the gap with epoxy, fixing the problem at least temporarily.

Initially, astronauts and other experts had suggested that the hole had been caused a by tiny rock that would have hit the space station and ripped a hole in it. "This leak seems to have resulted from a micrometeoroid impact," tweeted ISS veteran Scott Kelly in one representative tweet.

But strange reports are now emerging that suggest the leak could actually have been caused by a human. Russian reports citing anonymous sources suggest that the problem could have existed from the time the Soyuz capsule headed up to the International Space Station, and might have been treated with a temporary fix that has recently come undone.

Nasa has only said that the Russian space agency has "has convened a commission to conduct further analysis of the possible cause of the leak".

Russian news agency TASS reported that the boss of the Russian space agency, Roscosmos, said the theory that the hole was caused by an impact had been discounted.

"We are considering all the theories," Dmitry Rogozin, according to TASS. "The one about a meteorite impact has been rejected because the spaceship’s hull was evidently impacted from inside. However it is too early to say definitely what happened.

"But, it seems to be done by a faltering hand… it is a technological error by a specialist. It was done by a human hand - there are traces of a drill sliding along the surface. We don’t reject any theories."

He said that problem could have happened by accident or on purpose, and either on Earth or in space. A full investigation is being mounted to find the person responsible, TASS reported him as saying.

Both Nasa and Roscosmos stressed throughout the leak that the astronauts were in no immediate danger, and had been allowed to continue sleeping once the drop in pressure was recognised.

Once they were awake, astronauts worked with experts on the ground to find the hole and then to plug it up – initially, simply by placing a finger over the hole. Once it was fixed, pressure appears to have stabilised and the astronauts on board have gone back to their usual schedule.

The leak was traced back to the orbital part of the Soyuz capsule, which docked on the side of the International Space Station when it arrived. It is that capsule that astronauts are set to use to come back down to Earth, and work is ongoing to ensure the rest of the craft is safe.

The Independent

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