Update: January 11, 9:20AM AEDT: According to new reports, Kanai either fabricated this story, “mis-measured” himself, or it was all a joke that didn’t translate well to English. In a tweet posted yesterday, the Japanese astronaut apologised, claiming he had measured his height after the ISS captain questioned the apparent growth, and he had grown 2cm - a far cry from the 9cm previously claimed. “This mis-measurement appears to have become a serious topic, so I must apologise for this terrible fake news,” he tweeted. And he never explained how the original mistake occurred. “I am a little relieved to be able to ride on the return Soyuz,” Kanai added.
Norishige Kanai. (Image: NASA)
Sounds like an honest mistake; it’s doubtful an ISS astronaut like Kanai would willingly spew false information. Fair to say, however, that he needs to be careful next time he tweets something so extraordinary.
Below you’ll find our original post, “fake news” and all.
Microgravity environments do strange and often undesirable things to the human body, such as weakening muscles and bones, shrinking hearts, and flattening eyeballs. But it's also known to make astronauts a bit taller, as Norishige Kanai is now learning. The Japanese astronaut arrived at the ISS just three weeks ago and he's already grown an astonishing 9cm - and he's now worried that he won't fit into the seat of the Russian Soyuz return vehicle.
"Good morning, good morning," tweeted Kanai yesterday from the International Space Station. "Today there is a serious report... I had physical measurements since I got to space... [with] heights up to 9 centimetres! I grew like some plant in just three weeks, nothing like this since I was a junior high school student. I am a bit worried whether my body will fit in the return Soyuz seat."
Along with astronauts Scott Tingle and Anton Shkaplerov, Kanai arrived at the ISS on 17 December 2017 after launching from the Baikonur Cosmodrome in Kazakhstan.
Astronauts grow an average of between two and five centimetres in space, or about three per cent taller than their usual height. Astronauts get taller in space because the absence of gravity allows the vertebrae in their spines to spread apart. Nine centimetres is a lot, but as Libby Jackson of the UK Space Agency told BBC, "it is possible, knowing that every human body is different."
Kanai is scheduled to return to Earth in April. As to whether or not he'll fit into the seat of the Soyuz return vehicle, he's probably going to be just fine. According to NASA, the Russian Soyuz TMA descent module can accommodate astronauts as tall as 190cm. In his yesterday's tweets, Kanai said he's now roughly 182cm. He'd have to grow more than another 9cm for his height to become a problem. That doesn't seem likely, but given that he grew so much in just three weeks, who knows?
But it's a good thing the crew isn't using the old Soyuz descent capsule, the one used from 1986 to 2002 - a module that was only able to accommodate astronauts with a maximum height of 183cm.