It may be Christmas Eve, but today's a working day for the astronauts on the International Space Station. NASA's Rick Mastracchio and Mike Hopkins are conducting the second spacewalk in four days to repair the ISS's cooling system, and you can watch it live right here.

Today's mission is the second half of a job that started on Saturday, replacing a faulty ammonia pump in the cooling pipes that envelop the exterior of the ISS. The astronauts finished Saturday's spacewalk ahead of schedule, meaning they might get a little holiday break time if all goes well during the six-and-a-half hour repair job today. Sure, the scenery 230 miles above the earth isn't particularly seasonal — no flurries, no blinking lights, no tinsel in sight. But the out-of-this-world sight of spacewalking astronauts operating a 50-foot robotic arm will put wonder into anyone's day. [NASA TV]