NASA has announced plans for three spacewalks later this month to repair a faulty pump module that stopped working properly on December 11. The launch of a Cygnus spacecraft, scheduled for Thursday, has been postponed until at least January 13.

NASA plans for astronauts Rick Mastracchio and Mike Hopkins to perform spacewalks on December 21, 23 and 25 to replace the pump module with a spare. Mastracchio is a veteran of six previous spacewalks while this will be the first for Hopkins.

Read NASA's statement here.