Photos: Atlas 5 rocket aims for International Space Station

Now in the home stretch of a complex, multi-year upgrade, two space station astronauts floated outside the lab complex Thursday and pressed ahead with the third of four spacewalks the current crew is carrying out to complete the replacement of aging batteries in the station’s solar power system.

Two NASA astronauts will take part in the first all-female spacewalk this week, a critical outing to restore lost power in the wake of an equipment failure that cropped up after new batteries were installed in the International Space Station’s solar power system during two earlier spacewalks.

Ten commercial Earth-imaging satellites are mounted on top of a Rocket Lab Electron launcher for liftoff Wednesday from New Zealand.