The Christmas Eve spacewalk planned by NASA at the International Space Station should wrap up repair work on a faulty cooling line.
Mission Control said Monday that unless something goes awry, two astronauts ought to finish installing a new ammonia pump Tuesday, during a second spacewalk. NASA originally thought three spacewalks might be needed.
Astronauts Rick Mastracchio (Muh-STRACK-ee-oh) and Michael Hopkins removed the faulty pump during Saturday's spacewalk. Everything went so well, they jumped ahead.
The next spacewalk should have been Monday, but was bumped a day so Mastracchio could swap suits. He inadvertently hit the water switch in the air lock following Saturday's spacewalk, and engineers suspect water intruded into his suit.
NASA has conducted a Christmas Eve spacewalk only once before.
Explore further: Spacewalking astronauts make speedy station repairs (Update 2)