Two NASA astronauts are venturing outside the International Space Station (opens in new tab) 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 (opens in new tab), who arrived at the space station on SpaceX's Crew Dragon (opens in new tab) 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.
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This will be the second spacewalk for Cassidy and Behnken, who completed a 6-hour and 7-minute spacewalk (opens in new tab) 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 (opens in new tab). 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 (opens in new tab), which arrived at the station in May.
Email Hanneke Weitering at firstname.lastname@example.org or follow her @hannekescience. Follow us on Twitter @Spacedotcom and on Facebook.