Astronauts Stephen Bowen and Alvin Drew exiting the ISS
Media playback is unsupported on your device
Video

Discovery astronaut becomes 200th to go on spacewalk

An American astronaut has become the 200th person to walk in space during Discovery's final mission to the International Space Station.

Alvin Drew joined spacewalk veteran Stephen Bowen to install an extension cable and move a broken ammonia pump to a new storage location.

The pair will also open a small metal canister, destined for display in Japan, to expose its interior to outer space.

Go to next video: Discovery crew 'sad' to see shuttle retire