Video: Highlights of second Expedition 50 spacewalk

Two spacewalking astronauts working outside the International Space Station Friday completed work to replace aging batteries in one of the lab’s eight main solar power circuits. A second spacewalk next week, along with additional work with the station’s robot arm, will upgrade a second power channel.

Two space station astronauts are gearing up for a planned six-and-a-half-hour spacewalk Friday to replace a presumably shorted out solar array voltage regulator that knocked one of the lab’s eight power channels out of action late last year.

Expedition 45 commander Scott Kelly and flight engineer Kjell Lindgren have switched their spacesuits to battery power to begin planned six-and-a-half-hour spacewalk Wednesday outside the International Space Station.