Nasa cancels spacewalk after spacesuit coolant leak

Nasa cancelled a spacewalk for two astronauts on board the International Space Station for a second time after a coolant leak was discovered in a spacesuit.

Tracy Dyson and Mike Barratt were scheduled to venture outside the ISS to perform maintenance tasks on Monday, after the spacewalk was pushed back from June 13 when Nasa was informed of a "discomfort issue" with a spacesuit.

“The spacewalk for today has been cancelled due to a spacesuit cooling unit water leak that began right after the suits were put on internal battery power,” the broadcaster in Nasa's live stream said.

“The crew is now moving back into the airlock and closing that EV hatch [used by astronauts to enter and exit the station] and they will begin the repressurisation.”

The leak in Ms Dyson's suit was discovered after the crew put on their spacesuits and prepared to begin the spacewalk. "It's a little snowy in here, but not as bad as it was. I have ice on my gloves still and on my helmet a little bit," she told mission control.

The astronauts were to complete the removal of a faulty electronics box from a communications antenna during the spacewalk. They were also to collect samples for research into how microorganisms survive and reproduce on the exterior of the orbiting laboratory.

Nasa's spacesuits, many of which have been in use since the Space Shuttle era – between the 1980s and 2010s – are increasingly prone to malfunctions.

Over the years, issues including cooling system leaks and limited mobility have highlighted the need for updated designs and improved technology.

In 2013, Italian astronaut Luca Parmitano faced a dangerous water leak in his helmet during a spacewalk. The incident affected his vision and hearing and forced him to cut the spacewalk short.

Delays have also affected two Nasa astronauts who arrived at the ISS on a Boeing Starliner test flight in May. Their return has been postponed several times and is now set to happen in July.

Boeing were to use the delays to study several technical issues on the Starliner capsule, including helium leaks and thruster failures.

The capsule was rescheduled to return on June 26, but that was postponed so the spacewalk could take place before the vessel began its return to Earth. Boeing has insisted the "spacecraft remains cleared for return in case of an emergency on the space station".