Astronauts squeeze in last spacewalk before SpaceX departure

Astronauts have squeezed in one last spacewalk before turning their attention to the all-important end to SpaceX’s first crew flight.
Nasa’s Bob Behnken and Chris Cassidy floated out of the International Space Station on their fourth and final spacewalk in under a month. Instead of swapping batteries, they had to route cables, hook up a tool storage chest and perform other maintenance.