• Question: If gravity is not acting upon a person (like an astronaut) will the height of the person increase? If yes Why?

    Asked by dagikusa to Alice, Bose, Christian, Emma, Steve on 9 Mar 2016.
    • Photo: Steve Marsden

      Steve Marsden answered on 9 Mar 2016:

      Indeed it would. This is a problem that has to be dealt with on the International Space Station. Every day when you walk around, the spongy bits in your spine are compressed. In space, not having to walk leads your spine to expand slightly, which could be problematic when you arrive back on Earth. This can be quite a large change, with astronauts gaining up to 8 cm in height!

      To counteract this, the astronauts must wear compression suits before returning. This apply a pressure over the entire body, helping to compress the spine as it would be on Earth.

    • Photo: Emma Dean

      Emma Dean answered on 9 Mar 2016:

      Did you know that a person is on average 1cm taller in the morning than at night? It’s because when we lay down for long periods of time, the spongy bits in our spine start to expand back to their natural shape. As we spend most of our days in the upright position, gravity compresses them again, making us shorter.

Comments