Two NASA astronauts are venturing outside the International Space Station for a spacewalk today (July 1) to finish replacing old batteries on the station's solar arrays.
Expedition 63 Cmdr. Chris Cassidy and Demo-2 astronaut Bob Behnken, who arrived at the space station on SpaceX's Crew Dragon spacecraft in May, began at 7:13 a.m. EDT (1113 GMT) and will spend up to seven hours working in the vacuum of space.
- FAQ: How do astronauts take spacewalks?
- In photos: The amazing spacewalks of Expedition 61
- In photos: SpaceX's historic Demo-2 test flight with astronauts
This will be the second spacewalk for Cassidy and Behnken, who completed a 6-hour and 7-minute spacewalk together on June 26. During that spacewalk, the duo swapped out three old nickel-hydrogen batteries on the far starboard truss (S6 Truss) of the station for two more efficient lithium-ion batteries. Today, they will swap out one more battery and wrap up power upgrades that began in 2017. These batteries are designed to power the station through the end of its planned lifetime in 2024.
The new lithium-ion batteries that Cassidy and Behnken are installing arrived at the International Space Station on Japan's HTV-9 cargo resupply spacecraft, which arrived at the station in May.
Email Hanneke Weitering at email@example.com or follow her @hannekescience. Follow us on Twitter @Spacedotcom and on Facebook.