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Why cant u go to outer space like an upwards climbing roller coaster?

  1. Aug 15, 2008 #1
    when you reach that part 'which the earth can no longer hold onto you'.. wouldn't u just climb up and then bam.. your floating?
  2. jcsd
  3. Aug 15, 2008 #2


    Staff: Mentor

    Sure, the idea is called a skyhook, but we don't have the materials to build one.
  4. Aug 15, 2008 #3


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    Staff: Mentor

    We have enough trouble building half quarter mile tall structures!

    Note also - this only works for geostationary orbit, which is an altitude of around 24,000 miles. Low earth orbit is a paltry 150 miles, and at that low altitude, the speed of the orbit is by far the main energy requirement.
  5. Aug 15, 2008 #4

    D H

    User Avatar
    Staff Emeritus
    Science Advisor

    There is no place in which "earth can no longer hold on to you." Earth's gravity extends out to infinity. Gravity is an inverse square law, which means that gravitational acceleration is proportional to the inverse of the square of the distance to the center of the Earth. For example, the gravitational force on those astronauts you see on TV floating around in the space station is more-or-less the same as the force they are subject to when standing on the surface of the Earth -- specifically, its about 90% of the Earth-bound force.
  6. Aug 15, 2008 #5
    It'd be awesome if we did...
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