After just an hour of what should have been a six-and-a-half-hour spacewalk, an astronaut's helmet leak forced NASA to cancel the mission on the International Space Station this morning.

NASA astronaut Chris Cassidy and Luca Parmitano of the European Space Agency, both flight engineers, were scheduled to prepare the space Sstation for the addition of a Russian multipurpose laboratory module. They were planning to replace a video camera, move wireless television camera equipment and reconfigure thermal insulation over a failed electronics box.

U.S. astronaut Karen Nyberg assists Italian astronaut Luca Parmitano after water began building up inside his helmet during a spacewalk outside the International Space Station. (Photo: NASA via Reuters)

Most of the work had to be shelved for today and NASA said controllers will reschedule the work into future spacewalks.

The trouble began around 9 a.m. today when Parmitano reported that there was water floating behind his head inside his helmet, according to NASA. A leak in his helmet was causing the trouble.

While the leak didn't pose an immediate hazard to the astronaut, NASA's mission control scrubbed the spacewalk anyway.

The space agency also noted that today's abbreviated spacewalk was the second shortest in the history of the space station. This was the 171st spacewalk at the station, totaling 1,075 hours and 22 minutes of work outside the orbiting station.

Today's spacewalk was the third to prepare for the new Russian module.

On July 9, Cassidy and Parmitano completed a spacewalk that lasted a little more than six hours. On that walk, they replaced a space-to-ground transmitter that had failed in December and they began to route power cables for the addition of the Russian module. They also removed a failed camera assembly and installed power redundancy cables.

In June, two cosmonauts completed their own spacewalk to prepare for the coming Russian module. The addition is set to replace an older airlock with a combination research facility, airlock and docking port that will be brought to the space station on a Proton rocket later this year, according to NASA.

This article, Astronaut's leaking helmet forces NASA to scrub spacewalk, was originally published at Computerworld.com.

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