Two NASA astronauts have ventured out of the International Space Station (ISS) as part of the 229th spacewalk.
Astronauts Chris Cassidy and Robert Behnken departed the ISS at 07:35 EDT (12:35 BST) today, and their spacewalk is expected to last around seven hours.
During that time, the pair will complete battery replacement activities to upgrade one of two power channels on the station.
NASA explained: “The upgrade includes removing six ageing nickel-hydrogen batteries and replacing them with three new lithium-ion batteries and the adapter plates that complete the power circuit to the new batteries.”
NASA has now started its live coverage of the event.
The live stream is embedded at the top of this story, or you can watch it on NASA’s YouTube channel here.
The astronauts are now at the far end of the station's starboard truss preparing to swap batteries near the main solar arrays.
During the spacewalk, the astronauts will also route power and ethernet cables in preparation for the installation of a new external wireless system.
This will increase helmet coverage for astronauts on future spacewalks.
NASA added: “To support future power system upgrades, they also will remove a device called an “H-Fixture” that was installed before the solar arrays were launched to the space station.”
Mr Cassidy is wearing a spacesuit with red stripes during the spacewalk, indicating that he is Crew Member 1.
Meanwhile, Mr Behnken is wearing a spacesuit with no stripes, indicating that he is Crew Member 2.
This is the 229th spacewalk from the ISS, and the eighth spacewalk for each astronaut.
