NASA astronaut Mark Vande Hei will remain on the International Space Station until March, giving him a record-setting spaceflight.
The mission extension, which was predicted before Vande Hei's abrupt launch in April, will see the veteran astronaut spend about 353 days living and working on the orbiting laboratory, according to a tweet the astronaut posted on Tuesday (Sept. 14). That will break the existing record for longest single spaceflight by an American astronaut: 340 days, currently held by Scott Kelly.
"Honestly, it's exciting," Vande Hei said in a video clip filmed on the space station.
"I think all astronauts are explorers at heart," he added. "I'm looking forward to, as a human being, understanding how it feels to do something like this."
In the video, Vande Hei explains that he sees the extended stay as a crucial way for scientists to begin to understand how the human body withstands the long spaceflights that will be necessary to visit deep-space destinations like Mars.
Typically, space station visits last about six and a half months; a round trip to Mars would likely take more like two years, according to NASA.
"Thank you, Mark, for your dedication to @NASA and research that will prepare humanity for Artemis missions to the moon and later to Mars!" NASA Administrator Bill Nelson wrote in a tweet congratulating the astronaut on his mission extension.
The announcement comes three weeks after NASA delayed a spacewalk due to a medical issue, which was later revealed to be a pinched nerve in Vande Hei's neck. Vande Hei, who was originally scheduled to join the sortie, was replaced by Japan Aerospace Exploration Agency astronaut Akihiko Hoshide; Vande Hei supported the activity from inside the space station.
The mission extension isn't a surprise, however, as Vande Hei made clear during his video remarks. "My family's been braced for this, I've been braced for this, it's something that we expected," he said, noting that he is meditating every day and speaking with his family almost every day in order to manage the isolation that comes with long-duration spaceflight.
The lengthened stay is possible because of a short flight that NASA's Russian counterpart, Roscosmos, is launching next month. On Oct. 5, a veteran cosmonaut, an actor and a director will climb aboard a Soyuz capsule in order to spend about two weeks on the orbiting laboratory filming a movie dubbed "Challenge." Those two passengers will in effect fill Vande Hei's seat, as well as that of his Russian crewmate, Pyotr Dubrov, who will also remain in orbit until March.
The "Challenge" flight has been in the books since before Vande Hei publicly got his seat assignment. NASA, concerned by delays in Boeing's troubled Starliner crew capsule program, arranged to add Vande Hei to the Soyuz vehicle that launched in April, announcing the flight just a month before launch.
Although the mission extension will see Vande Hei jump to the lead of NASA's long-duration flight veterans, the astronaut said that the record isn't about him and he doesn't expect to rest on the laurels it might bring him.
"I don't think it's a record that I would even attribute to me, it's a record that I would attribute to our space program," Vande Hei said. "I expect this record to be broken, and that will be a further success for our space program."
Email Meghan Bartels at firstname.lastname@example.org or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.