Updated at 7.52pm

THE DISCOVERY OF water in a US astronaut’s helmet brought an early end today to the first ever galactic walkabout by his British colleague, astronaut Tim Peake, Nasa said.

“A small water bubble” in American Tim Kopra’s helmet led mission control to wrap up about two hours early out of an abundance of caution, Nasa commentator Rob Navias said.

The situation brought back memories of a harrowing emergency in 2013 when Italian astronaut Luca Parmitano’s helmet began rapidly filling with water and risked drowning him.

“This is nowhere near as severe as that incident was,” said Navias, as he narrated Kopra’s return to the airlock live on Nasa television.

“The crew was never in any danger.”

Kopra, 52, had reported a high carbon dioxide reading in his spacesuit earlier in the outing, but felt no symptoms, and mission control decided the alarm was due to a faulty sensor.

The liquid showed up about four hours into the six-and-a-half-hour spacewalk.

Kopra said the water, which tends to glob together in space, was about 10 by five centimeters.

“The size was a concern,” NASA chief astronaut Chris Cassidy said, after the crew was safely inside.

The pair had been planning to replace a failed power unit on the space station.

Hoisting a rectangular voltage regulator that would weigh 200 pounds on Earth, Peake had to manoeuvre more than 200 feet out of the International Space Station airlock to the worksite.

In his blog ahead of today’s excursion, he said:

Although I am exhilarated by tomorrow’s spacewalk I have no time to dwell on these emotions. The six hours and thirty minutes we will work on the Space Station’s hull are meticulously planned and Tim and I need to execute each step methodically.

The pair have been training for months for this specific walk.

“However, to undertake an EVA actually takes several years of training,” added the Briton. “We have spent many hours working in our spacesuits, ‘floating’ in the largest swimming pool on Earth with a Space Station mockup.

We have used virtual reality headsets to re-enact our operations and trained for the worst case scenario of becoming detached from the Space Station but I guess nothing can fully prepare for the feeling of being outside of a spacecraft in the vacuum of space.

With reporting by AFP. Originally published 1.13pm

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