• Question: why is there less gravity in space?

    Asked by ZAK.T! to Heather, Helen, Hugh, Jane, Julian on 14 Nov 2014. This question was also asked by HannahD.
    • Photo: Julian Onions

      Julian Onions answered on 14 Nov 2014:

      Well – there are sort of two parts to this.
      The first is the power of gravity gets smaller as you move away from the body that is making it. So the further you get from the Earth, the less the gravity – in facts its whats called an inverse square law, so it gets to a 1/4 of the power for every doubling of the distance.

      However there is also the weightlessness that astronauts feel, and this is because they are in orbit, and effectively always falling towards the Earth but missing it. So they and the space craft are dropping at the same rate, so they don’t feel the gravity, although it is still there really.

    • Photo: Helen Johnson

      Helen Johnson answered on 16 Nov 2014:

      Exactly. If there is no overall force acting on you, then there is no acceleration (you’re in free fall) and you don’t feel gravity. You can create an artificial sort of ‘gravity’ by having a rotating spacecraft (like in the film Interstellar, and other scifi) – the rotation makes you feel a force to the outside of the ring, and keeps your feet down on that part of the craft.

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