Down to the Wire for Station Repair Spacewalks, CBS

"NASA astronauts and engineers are refining plans for two spacewalks by astronauts Douglas Wheelock and Tracy Caldwell Dyson to replace a large ammonia pump module that shut down Saturday, knocking out one of the International Space Station's two cooling loops. The astronauts hope to carry out the first spacewalk Friday morning, starting at 6:55 a.m. EDT, and a second excursion Monday to finish the job, one of the so-called "big 14" on a list of critical components that require spacewalk repair if problems crop up. NASA managers initially targeted Thursday for the first spacewalk and Sunday for the second, but decided late Monday they needed more time to review procedures."

International Space Station Repair Spacewalk Planned for Friday

"NASA has decided to wait until Friday to conduct a spacewalk to replace a failed ammonia pump module on the International Space Station. Mission managers, program managers, flight controllers, engineers, astronauts and spacewalk experts made the decision Monday evening after continuing to analyze and refine engineering requirements, and reviewing the results of an underwater practice session."