(AP) — NASA astronauts are taking a spacewalk to rearrange space station plumbing and tackle other odd jobs. The work should have been completed during a spacewalk outside the International Space Station a week ago. But power upgrades took longer than expected. So NASA decided to give Victor Glover and Mike Hopkins a bonus spacewalk Saturday to get everything done. The two teamed up 1 1/2 months ago for back-to-back spacewalks. This time, they need to vent a couple of ammonia jumper lines that are part of the external cooling system. They’ll be extra careful to avoid getting any toxic ammonia coolant on their suits.