Video: Expedition 50 spacewalk highlights

Two Russian cosmonauts stepped outside the International Space Station Wednesday, sent birthday greetings to former cosmonaut Alexey Leonov, the first man to walk in space, and then carried out a full slate of maintenance work.

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.

This is a narrated animation previewing the steps and activities to be performed by the International Space Station astronauts during the battery replacement spacewalk on Jan. 13.