Mr Kanai tweeted: "Good morning, everybody". I have a major announcement today. Nothing like this since high school. "I am a bit anxious whether my body will fit in the return Soyuz seat".
A few hours later, Kanai tweeted that his captain said the 9 cm spurt seemed wrong, and that after remeasuring, he found he'd only grown 2 cm, well within the normal range.
Certainly, many of us would love the opportunity to grow a little taller, so the thought of enjoying a natural stretch might be initially appealing. Flight Commander Shkaplerov would know these things, he's such a veteran.
When asked if Kanai should be concerned about making it back to Earth, Anderson said he is not anxious because once you return to Earth your spine shrinks back to normal. This extra growth may actually be a major problem, and has the astronaut concerned that he might not actually be able to fit into the Soyuz capsule which is meant to carry him back to Earth.
This is the first space mission for the Japanese astronaut who was previously a diving medical officer with the Japan Maritime Self-Defense Force.