Basic Astrodynamics: Understanding Total Energy

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The discussion centers on the total energy of a satellite in different orbits, highlighting that total energy is lower at higher altitudes due to decreased speed and increased height. A key point is the understanding that potential energy is negative, which impacts total energy calculations. Participants clarify that total energy is indeed higher in a higher orbit when correctly accounting for kinetic and potential energy. One user acknowledges a calculation error that led to initial confusion. The conversation emphasizes the importance of accurately applying classical equations in astrodynamics.
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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?
 
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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?
 
You are right, I searched and found a calculation error - thanks.
 
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