VIDEO: Expedition 42-43 mission preview

Europe’s fifth and final Automated Transfer Vehicle departed the International Space Station for the last time Saturday, closing out one of the European Space Agency’s flagship programs as the bus-sized spaceship heads for a destructive re-entry Sunday.

Two NASA astronauts and an Italian flight engineer are sheltering in the space station’s Russian segment as mission control analyzes a possible leak of toxic ammonia coolant aboard the complex.

Astronauts Barry “Butch” Wilmore and Terry Virts floated outside the International Space Station Saturday and installed wiring needed for two new docking mechanisms that will be attached later this year for use by Boeing and SpaceX crew capsules.