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Construct a maglev launch system on our moon

  1. Jun 6, 2003 #1


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    Gold Member

    if were posible to construct a maglev launch system on our moon how
    much energy would be required to launch shutle sized space craft?
    Last edited by a moderator: Feb 5, 2013
  2. jcsd
  3. Jun 6, 2003 #2


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    Science Advisor

    Greetings wolram !
    Take the kinetic energy and devide it by 3
    (in the more pessimisitic case) or by 1.5 (in the
    optimistic case) to account for efficiency.

    E = Ek / eff = Ms * V^2 / 2 / eff

    Ms(without fuel and boosters) = 9,000 kg = 20,000 pounds
    V (for low lunar orbit, if I remember correctly the
    approximate value) = 2 km/sec = = 1.25 miles/sec

    E would be 27*10^9 - 54*10^9 J .

    In addition we need to substract the gravity of the
    moon during the acceleration but if the acceleration
    is sufficiently fast it will have a small effect that
    we can ignore in this approximation.

    If the acceleration is a = 30 m/sec^2 = 100 ft/sec^2 = 3g
    then the power output during the acceleration process
    (P = E / t) would be about 400 - 800 MW.

    Live long and prosper.
  4. Jun 21, 2003 #3
    Why divide? Did you mean multiply, or am I missing the boat here?
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