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Space shuttles descent temperatures

  1. Oct 6, 2005 #1
    Does a planet's atmosphere effect the temperature spacecrafts generate when descending from orbit?
  2. jcsd
  3. Oct 6, 2005 #2
    Hi Randi and welcome.

    Would you think that a pebble thrown in the pond will ripple the water for long? Likewise I don't think that the atmosphere will notice a lot of a descending space craft. Just a little bit, locally and very short.

    The answer, my friend, is blowing in the wind. :wink:
  4. Oct 6, 2005 #3


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    Staff Emeritus
    Science Advisor

    Quite possibly is does if the heating generation and dissipation are functions of the mean molecular mass and molecular density of the atmosphere.

    The heat is generated because a spacecraft is transfer its kinetic energy to the atmosphere. The energy is dissipated as a momentum transfer to atmosphere but also as heat in the heat shield, which may be primarily by radiation.

    Presumably a denser atmosphere can slow a spacecraft more quickly than a thin atmosphere, and perhaps would produce a greater heating rate on the thermal shield. A predominantly CO2 atmosphere would give a different deceleration than the earth's atmosphere of N2 and O2 all else the same. Unfortunately, I don't have any detailed equations, so I can't answer the question quantitatively. One would have to know how the atmospheric composition and density affect the radiative and conductive heat transfer rates, well as the heat generation rate.
  5. Oct 8, 2005 #4
    Thanks, it's nice to be here.
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