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Basic Astrodynamics

  1. Nov 11, 2015 #1
    Using the well established classical equation to determine the sum of kinetic and potential energies of a satellite at two different altitudes, the result is a lower total energy at the higher altitude. Since the speed is less and the height is greater I think I understand this result. Yet I would have thought it would take more energy to place a satellite in a higher orbit. What am I missing in this understanding?
  2. jcsd
  3. Nov 11, 2015 #2


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    I think you've made a mistake. The total energy is in fact higher in a higher orbit. Remember that the potential energy is negative. Can you write down the kinetic, potential, and total energy for a circular orbit as a function of r?
  4. Nov 11, 2015 #3
    You are right, I searched and found a calculation error - thanks.
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