Watch NASA astronauts collect microbe samples during ISS spacewalk today (livestream video)

Three astronauts, two in spacesuits, test spacesuits for a spacewalk on the International Space Station
NASA astronaut Tracy Caldwell Dyson (center) checks the spacesuits of NASA crewmates Michael Barratt (right) and Matthew Dominick during spacewalk preparations on the International Space Station on June 5, 2024. (Image credit: NASA)

Editor's note: The spacewalk was cancelled at 8:52 a.m. EDT (1252 GMT) due to a spacesuit coolant leak while the astronauts were still in the hatch. The spacewalk lasted 31 minutes and the crew was never in any danger. Read our story about it here.

Two NASA astronauts will venture outside the International Space Station today (June 24) for a delayed spacewalk and you can watch it live online for free.

NASA astronauts Tracy Caldwell Dyson and Mike Barratt will perform the spacewalk, or extravehicular activity (EVA). The livestream started at 6:30 a.m. EDT (1030 GMT). 

The spacewalk is scheduled to start at 8 a.m. EDT (1200 GMT) and last about 6.5 hours, although at the time of this story at 8:35 a.m. EDT (1235 GMT), depressurization was ongoing. (Spacewalk timing is always approximate as operational needs come first.)

You can watch the International Space Station (ISS) action on this page and the homepage, courtesy of NASA, or live via the space agency.  (You can read more about spacewalks and how they work on our EVA reference page.)

NASA postponed the first attempt for this spacewalk on June 13 due to a "spacesuit discomfort" issue with Matt Dominick. The agency elected to change out Dominick with Barratt as the spacesuits on board are already sized for Barratt, and to decide later who to schedule for a scheduled July 2 spacewalk.

Related: NASA calls off spacewalk at International Space Station due to 'spacesuit discomfort'

During their spacewalk, the duo will retrieve a faulty piece of communications equipment, known as the radio frequency group. Dyson will also swab the exterior of the space station to gather samples for a study of microorganisms in extreme microgravity environments. 

"There is a group of scientists that's very interested in this, for example, for going to Mars and understanding what we might carry with us to the Martian surface — accidentally discovering something on the Martian surface that actually came from us, that kind of thing," Dina Contella, NASAs deputy program manager for the International Space Station, said Tuesday (June 11) during a spacewalk-previewing press briefing.

Monday's EVA is the first of two upcoming spacewalks geared toward ongoing science and maintenance of the orbital laboratory. (NASA originally planned three, but reduced it to two after the June 13 attempt as there are other space station scheduling needs to consider as well, like spacecraft arrivals.)

Having a spacewalk on the docket  affected the schedule for the first-ever astronaut mission of Boeing's Starliner capsule, called Crew Flight Test (CFT).

CFT launched with NASA astronauts Butch Wilmore and Suni Williams on June 5. The duo rendezvoused and docked with the ISS a day later, and were scheduled to stay aboard for about a week. Their mission was postponed to make room for the June 13 spacewalk.

But Wilmore and Williams had their mission extended several times, including on Friday (June 21), and are now expected to return after the July 2 spacewalk. The primary reason for the June 21 delay, however, is to allow Wilmore, Williams and ground teams to perform additional checks of Starliner before the shakedown flight parachutes back down to Earth.

Editor's note: This story was updated at 8:35 a.m. EDT June 24 with information about the rescheduled spacewalk.

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Josh Dinner
Writer, Content Manager

Josh Dinner is's Content Manager. He is a writer and photographer with a passion for science and space exploration, and has been working the space beat since 2016. Josh has covered the evolution of NASA's commercial spaceflight partnerships, from early Dragon and Cygnus cargo missions to the ongoing development and launches of crewed missions from the Space Coast, as well as NASA science missions and more. He also enjoys building 1:144 scale models of rockets and human-flown spacecraft. Find some of Josh's launch photography on Instagram and his website, and follow him on Twitter, where he mostly posts in haiku.