Enveloped by the vast expanse of the cosmos, NASA astronauts Rick Mastracchio and Mike Hopkins set about repairing the cooling system of the ISS on Saturday. The spacewalking duo worked so quickly that they completed the day's planned tasks with time to spare and, thus, tackled additional steps of the repair job. As such, the originally expected third spacewalk for the project, scheduled to happen on Christmas Day, may now no longer be required. More on the story at Space.com.