Absolute coordinate system of GPS satellites

Discussion in 'General Science & Technology' started by Saint, Dec 31, 2019.

  1. Saint Valued Senior Member

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    What is the absolute coordinate system of GPS satellites?
    Is it the center of the earth?
     
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  3. origin In a democracy you deserve the leaders you elect. Valued Senior Member

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    That is determined by scientists and you think scientists are liars so it the answer is irrelevant.
     
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  5. James R Just this guy, you know? Staff Member

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    Not sure. What do you mean by an absolute coordinate system?
     
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  7. Michael 345 New year. PRESENT is 70 years old Valued Senior Member

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    Fairly certain not centre of Earth

    I know London, guess most other large cities, have nominal centres, London being

    The coordinates of the nominal centre of London, traditionally considered to be the original Eleanor Cross at Charing Cross near the junction of Trafalgar Square and Whitehall, are about 51°30′26″N 00°07′39″W.

    https://en.m.wikipedia.org/wiki/London

    Also a plaque may mark the centre from which distances can be calculated to other parts of the city

    https://gssc.esa.int/navipedia/index.php/Satellite_Coordinates

    This link provides some details about satellite coordinates

    The app I have in my phone requires 3 satellites to be in view before it will locate within a few metres my house

    Uber makes good use of the system showing me the car which has accepted my request, shows on a roadmap where the car is and tracks its travel

    Please Register or Log in to view the hidden image!

     
  8. RainbowSingularity Valued Senior Member

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    a question about the evolution of a round earth ?
     
  9. Saint Valued Senior Member

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    After major earthquake, will the plate coordinates be shifted?
     
  10. RainbowSingularity Valued Senior Member

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    i thought you did not believe in science ?
     
  11. James R Just this guy, you know? Staff Member

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    Possibly.

    How do you think that the average rate of continental drift is determined for the various tectonic plates?
     
  12. Halc Registered Senior Member

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    None of the coordinate systems mentioned are absolute.
    If center of Earth is used, then it is relative to that accelerating coordinate system, not absolute. Earth is hardly an inertial object.

    No, I am personally unfamiliar with the details of programming of GPS and what coordinate system might be used for the computations.
    Center of Earth seems a reasonable choice in my opinion.
     
  13. spidergoat Liddle' Dick Tater Valued Senior Member

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    It's the system of longitude and latitude established long ago with Greenwich, London at its center. This position system is coordinated with satellites using more than 8 tracking stations around the world, who's locations have been precisely established using other methods.

    While a single tracking station could move due to plate tectonics, it's role would just be removed temporarily until it's new location was established.
     
  14. Saint Valued Senior Member

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    if one or two of the satellites break down, what will happen?
     
  15. Janus58 Valued Senior Member

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    There are 9 satellites held in reserve. If a
    satellite fails, one of them will take up the slack. A new satellite will be launched in order to get the number of reserve satellites back up to 9.
     
  16. Saint Valued Senior Member

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    which country pays for the satellite cost?
     
  17. spidergoat Liddle' Dick Tater Valued Senior Member

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    It's primarily a US system. There is a separate Russian system, and the data can be combined for greater accuracy. Satellites are regularly taken off line until their positions can be corrected.
     
  18. Saint Valued Senior Member

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    Do the satellites have commercial values to make money by providing services to broadcasting companies?
     
  19. Janus58 Valued Senior Member

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    GPS satellites, which orbit with periods of 12 hours would not make good communication satellites. Those orbit at geosnyc altitudes, which are a good deal higher.
     
  20. spidergoat Liddle' Dick Tater Valued Senior Member

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    GPS is a free service provided by the US government to help general commerce. Also there are military applications.
     

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