News / World

Astronomical oops: Japanese astronaut didn't grow nine centimetres after all

Norishige Kanai's spine only stretched two centimetres, according to the astronaut himself. The earlier report of 9 cm was due to a measuring error.

Japanese astronaut Norishige Kanai, a member of the main crew to the International Space Station (ISS).

Dmitri Lovetsky / AP POOL

Japanese astronaut Norishige Kanai, a member of the main crew to the International Space Station (ISS).

The news of a Japanese astronaut who shot up nine centimetres in height after just a month in spaceflight turned out to be too out-of-this-world to be true.

On Jan. 8 Norishige Kanai, a 41-year-old rookie astronaut with JAXA, Japan’s space agency, tweeted his shock that he had measured 9 cm taller than on the day of his departure.

A few hours later, Kanai tweeted that his captain said the 9 cm spurt seemed wrong, and that after remeasuring, he’d only grown 2 cm, well within the normal range.

Christina Laffin, professor of Japanese Literature at UBC, was kind enough to provide this translation of his correction:

"Living without gravity for a while expands the gaps between vertebrae, enabling an increase in height. Depending on the person, some may experience back pain as a result. The Russian captain was dubious about anyone growing a full nine inches so I measured myself again and found my height to be 182 cm--only two centimetres more than my regular height on earth."

(Google translate made wretched work of his casual Japanese, making it necessary for us to get a fluent speaker to confirm the story.)

Late Tuesday evening — early morning, Japan time — Kanai apologized for the spread of “fake news” that spread all over the global media when he was presumably asleep. His initial correction was not widely picked up.

Kanai has been on a mission to the International Space Station since Dec. 17 and is expected to stay until June. It's normal for astronauts' spines to straighten and stretch during spaceflight in an environment of microgravity, but nine centimetres — nearly four inches — would be extraordinary. According to orthopedic surgery professor Douglas Chang, who has studied changes to bone structure in space, 6.6 cm is considered a high amount of growth, and 5 cm is average.

To learn more about why astronauts get taller temporarily in space — and why that’s a big problem for those who want to go to Mars — pick up a Metro or check out this coming Friday for a feature in Metro Science.

More on