Astronaut medical issue forces NASA to call off spacewalk at space station

NASA astronaut Mark Vande Hei on a spacewalk outside the International Space Station in 2017.

NASA astronaut Mark Vande Hei on a spacewalk outside the International Space Station in 2017.  (Image credit: Randy Bresnik/NASA/Twitter)

NASA has called off plans for a spacewalk outside the International Space Station this week due a medical issue with one of the astronauts due to join the excursion, agency officials said Monday (Aug. 23). 

A "minor medical issue" involving NASA astronaut Mark Vande Hei is the reason for the spacewalk's postponement, the U.S. space agency wrote in an update. Vande Hei and crewmate Akihiko Hoshide of the Japan Aerospace Exploration Agency (JAXA) were scheduled to venture outside the station on Tuesday (Aug. 24) to prepare the orbiting lab for a new solar array. 

"This issue is not a medical emergency," NASA officials wrote in the update. "The spacewalk is not time-sensitive and crew members are continuing to move forward with other station work and activities."

Video: New roll-out solar arrays deployed on space station
Related: The International Space Station: inside and out (infographic)

NASA astronauts Meghan McArthur (left), Shane Kimbrough (top center), Mark Vande Hei (bottom) and French astronaut Thomas Pesquet of the European Space Agency review spacewalk preparations on June 10, 2021. (Image credit: NASA)

NASA teams are now working to determine when to reschedule the spacewalk amid a busy time for the space station. A SpaceX Cargo Dragon spacecraft is currently set to launch the CRS-23 resupply mission to the station for NASA on Saturday (Aug. 28). Russia, meanwhile, is planning to send cosmonauts out on a series of spacewalks beginning next week to complete installation work on the station's newest Russian module, called Nauka, which docked at the station earlier this month.

During the planned spacewalk, Vandei Hei and Hoshide were to install a modification kit on the port side of the space station's backbone-like main truss. The kit will allow the installation of a new type of solar wing, called the International Space Station Roll-Out Solar Array, to beef up the station's power grid. The new array will be the third of six new solar wings to upgrade the station's power system.

That solar array prep work, along with other tasks, will now have to wait until a new spacewalk time is determined, NASA officials said.

Email Tariq Malik at or follow him @tariqjmalik. Follow us @Spacedotcom, Facebook and Instagram.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at:

Tariq Malik

Tariq is the Editor-in-Chief of and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.