TIM Peake’s historic first walk in space was ended early after a water bubble was detected in the helmet of his colleague Tim Kopra.
The British astronaut helped complete the crew’s primary task of repairing a broken voltage regulator and headed back to the airlock on the International Space Station (ISS).
Both astronauts were safe, according to the ISS.
Major Peake, 43, became the first Briton to ever complete a extra-vehicular activity (EVA) – or spacewalk – and was undertaking a maintenance operation with the American Colonel Kopra.
After the operation was terminated by the lead flight director, Major Peake and Colonel Kopra were told to spend some time cleaning up their tools before heading to safety.
The spacewalk, which had been set to last six-and-a-half hours, was ended around four hours and ten minutes in.
As a precaution, spacewalk terminated due to small amount of water in Tim’s helmetNASA
The National Aeronautics and Space Administration (Nasa) said the termination was a precaution.
Tweeting from its official account, it said: “As a precaution, spacewalk terminated due to small amount of water in Tim’s helmet.”
Earlier Major Peake, from Chichester, West Sussex, told of his pride in stepping into space with the Union flag on his space suit.
He is on a six-month mission with the European Space Agency (ESA). Live footage showed both astronauts safely returning to the airlock area of the ISS and the thermal cover being closed behind them.
Guided by ground staff in Houston, the pair successfully replaced the broken power box with a spare unit. They inspected the broken equipment and found no damage, meaning the fault was likely to be internal.
The astronauts performed a number of other maintenance tasks before being called back early.
After the duo were safely inside with the outer airlock hatch closed, Tim Peake thanked mission controllers: “You guys did a great job,” he said.
The space station’s other crew members, Nasa astronaut and station commander Scott Kelly along with Russian Space Agency (Roscosmos) cosmonauts Sergey Volkov and Yuri Malenchenko were on hand.
Once the inner hatch was open, they were expected to help the spacewalkers remove their suits and remove the water from Tim Kopra’s face. They would also use a syringe to collect a sample of the water and remove absorption pads from the inside of the helmet as evidence for investigators who will aim to determine the cause of the leak.
Earlier in the spacewalk, Col Kopra reported abnormal carbon dioxide readings from his suit. Ground controllers decided it was down to a sensor problem.