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High probe above surface

  1. Feb 25, 2013 #1
    How high is usually the probe above the surface of the cosmic body? It would be best if it was specifically the Tethys, but suffice average.

    Thanks and sorry for my bad English.
  2. jcsd
  3. Feb 25, 2013 #2

    Simon Bridge

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    You mean how far spacecraft get to the objects they are sent to look at?
    You know some of them land right? There is no "standard orbit" for spacecraft. If it has to travel further, then the closest approach is determined by it's kinetic energy, engines, and fuel (and the object in question).

    Tethys has been approached by several space probes including Pioneer 11 (1979), Voyager 1 (1980), Voyager 2 (1981), and Cassini since 2004.

    dmuller has timelines for spacecraft missions - here's the Tethys one:
    I don't think I believe the 1500km value for 2005-09-23 (Cassini) .. I'd believe 15000kms.

    That's really close - 15 Tethys diameters - a bit more than the diameter of the Earth.

    From Saturn, Cassini managed a long ellipse, if I'm reading that right, with the closest approach at 78000km (at insertion) and swinging out as far as 9100000km.
    There was a lot of manovering, according to the timeline - typically the closest was around 200000km and the farthest 2000000km.

    Real orbits are some way from the simple circles you learn in high school aye?
    Last edited: Feb 25, 2013
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