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Outer Space, object by itself

  1. Jul 18, 2014 #1
    Have a question i thought of regarding something in space, do objects float in space or are they sitting in a fixed position? Also is everything always moving in space regardless of being able to see something moving?
  2. jcsd
  3. Jul 18, 2014 #2


    Staff: Mentor

    Even though an object is in outer space, it is still affected by gravitational forces which cause it to move. The fact things appear to float is that they are local to each other and are affected by the same forces. This is like dropping two balls from a high place at the same time they fall together and they hit the ground together at the same time. If you were on one of the balls you might think its is floating next to you.
  4. Jul 18, 2014 #3


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    Staff Emeritus
    Science Advisor

    Position and movement are relative. This means that there is no such thing as an absolute fixed position, only a fixed position relative to another object. And remember that objects only "float" when they are mostly stationary relative to you. An asteroid "floats" relative to another asteroid moving with it, but it may be moving faster than a bullet relative to a space probe hurdling through the asteroid belt on its way out to Jupiter.
    If something is moving relative to you, it is moving regardless of whether you can see it or not. Same thing if it isn't moving relative to you.
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