One fringe benefit of an astronaut's trip to space: He or she returns to Earth taller (though only temporarily). That's thanks to the lack of gravity, which elongates the distance between the vertebrae in one's spine. And for one Japanese astronaut, the change has been more extreme than most. Norishige Kanai has exceeded the typical growth of roughly 0.75 inches to 2.0 inches (as this famed US astronaut did), saying he has instead grown 3.5 inches since reaching the International Space Station in mid-December. "I grew like some plant in just three weeks. Nothing like this since high school. I'm a bit worried whether I'll fit in the Soyuz seat when I go back," he tweeted.
The BBC explains the Soyuz spacecraft, which shuttles astronauts to and from Earth, does have a height limit, which the Washington Post reports is 6 feet, 3 inches. And while the Post notes Kanai's tweet about not fitting was probably made in jest, he likely wasn't joking about the extreme growth, Libby Jackson of the UK Space Agency tells the BBC. "[Three-and-a-half inches] is a lot, but it is possible, knowing that every human body is different." Vice wasn't able to track down how tall Kanai is on Earth, but does note the latest version of the Soyuz TMA capsule leaves extra breathing room: The limit of the version used until 2003 was 6 feet. (Read more International Space Station stories.)