Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

Astronauts Go On Spacewalk To Fix Ammonia Leak

In this image made from video provided by NASA, astronaut Christopher Cassidy, foreground, holds a power wrench as he stows away a coolant pump on the International Space Station on Saturday. Thomas Marshburn is at left.
AP
In this image made from video provided by NASA, astronaut Christopher Cassidy, foreground, holds a power wrench as he stows away a coolant pump on the International Space Station on Saturday. Thomas Marshburn is at left.

Two astronauts went on a last-minute spacewalk Saturday to replace a pump suspected of being the source of a serious ammonia leak.

It was unclear what caused the ammonia leak, NASA spokesman Rob Navias said, "but the installation of this spare pump package — at least at the moment — seems to have done the trick."

NASA officials called the spacewalk a success, but said it would take time to see if the leak was indeed stopped. Engineers will review photos the astronauts took at the site.

According to Spaceflight Now, the leak was in the system used to cool "one of eight electrical channels powered by the space station's main solar panels."

NASA said the leak never jeopardized the crew at the International Space Station, AP reports, but the agency wanted to fix the problem while it was fresh.

Our Original Post Continues:

As two astronauts make what The Associated Press writes is "a hastily planned spacewalk Saturday to try to fix an ammonia leak in the power system of the International Space Station," NASA is webcasting.

It's estimated they'll be working on the problem for about six hours. The leak is not presenting a danger, NASA says, and the space station still has plenty of power.

Update at 3:08. ET. : New Pump Installed

NASA says astronauts Chris Cassidy and Tom Marshburn replaced a pump controller box suspected of being the source of the ammonia leak. The Associated Press reports they uncovered "no smoking guns" responsible for the problem.

Copyright 2021 NPR. To see more, visit https://www.npr.org.

Mark Memmott is NPR's supervising senior editor for Standards & Practices. In that role, he's a resource for NPR's journalists – helping them raise the right questions as they do their work and uphold the organization's standards.