Two astronauts have gone outside the International Space Station to do some work. This is the first spacewalk of this mission. Two more are planned.
Garrett Reisman and Stephen Bowen are putting in a new antenna and a spare parts platform. This will take about six and a half hours.
The two left Earth on Friday on the space shuttle Atlantis, with four other crewmembers. They got to the ISS on Sunday.
This will be Atlantis' last mission.source
Image: NASA TV