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Satellite reentry

  1. Dec 15, 2008 #1
    The path of a satellite reentering the atmosphere from a very high orbit has two components, one gravitational and the other from the atmosphere. Could there be a discussion of the two separate components using Newtonian gravity with gravity as:

    g = GM/r^2

    that change with elevation as a function of time.
    Last edited: Dec 15, 2008
  2. jcsd
  3. Dec 15, 2008 #2
    There may also be a velocity component from the satellite's rotational velocity...anyway the atmosphere acts as a variable resistance (drag) in a direction opposite the velocity.

    the complication is that air resistance and gravity vary with altitude and air resistance varies with speed...and likely with temperature as well...

    Try wikipedia,

    and see "RE-ENTRY for a brief discussion of some practical considerations....it's not a simple theoretical situation underlying your question. For one thing, a satellite in free fall will burn up...

    There are practical equations for computing air resistance...I researched some for wind force on a boat while anchored...it varied as the square of wind speed...people had computed/measured constants for different boat shapes...
    Last edited: Dec 15, 2008
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