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Re: GPS satellites.

Cross-posted to 4 groups.

Followups directed to: sci.physics.relativity

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J.  Clarke amok-crossposted to 4 newsgroups:
^^
Your first name belongs there.

> On Mon, 09 Apr 2018 10:45:53 -0700 (Seattle), Jeff-Relf.Me  @. wrote:
>> GPS satellites are the perfect way to explain relativity,
>> because everyone can relate to it.
>>
>> On Earth, the satellite's signal is BlueShifted by gravity
>> and RedShifted by its velocity,

It is _not_ written “BlueShifted” or “RedShifted”.

>> relative to earth's core.
> 
> While that is true,

In a manner of speaking.  Because gravity does not exist in general 
relativity, and the satellites’ velocity is measured relative to the ground 
receiver (approximately, in the ECI frame, which has nothing to do with 
“earth’s core” but with the *center* of the *geoid* through which the 
planet’s rotational axis passes).

That is, while the signal from a satellite to the ground will always be 
blueshifted due to a positive difference in spacetime curvature, the signal 
can *equally* be blueshifted due to relative motion of the satellite 
*towards* the observer or vice-versa.

> the relativistic correction

There are many misconceptions regarding GNSSs like GPS (we have discussed 
them all here in sci.physics.relativity).  What do *you* mean by 
“relativistic correction”?

> in GPS satellites is in the timebase,

What do you mean by “timebase”?

> not the transmission frequency.

Correct.  Both the gravitational redshift/blueshift and the relativistic 
Doppler shift are negligibly small here.


F’up2 sci.physics.relativity

PointedEars
-- 
Q: Where are offenders sentenced for light crimes?  
A: To a prism.

(from: WolframAlpha)

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Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-08 20:02 +0100
  Re: The Speeed of Light Libor 'Poutnik' Stříž <poutnik@privacy.net> - 2018-04-08 22:03 +0200
    Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-05-05 22:16 -0500
  Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-08 18:10 -0700
  Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-09 09:39 -0500
    Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-09 16:04 +0100
      Re: The Speeed of Light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-09 18:16 +0200
        GPS satellites. Jeff-Relf.Me  @. - 2018-04-09 10:45 -0700
          Re: GPS satellites. "reber G=emc^2" <herbertglazier0@gmail.com> - 2018-04-09 11:33 -0700
            Re: GPS satellites. "hanson" <hanson@quick.net> - 2018-04-09 12:34 -0700
          Re: GPS satellites. J. Clarke <jclarke.873638@gmail.com> - 2018-04-09 23:28 -0400
            GPS satellites. Jeff-Relf.Me  @. - 2018-04-09 20:49 -0700
            Re: GPS satellites. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-10 06:00 +0200
            Re: GPS satellites. Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-11 14:36 -0500
              Re: GPS satellites. J. Clarke <jclarke.873638@gmail.com> - 2018-04-11 22:22 -0400
                Re: GPS satellites. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-12 04:38 +0200
      Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-09 09:51 -0700
      Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-09 14:00 -0500
      Re: The Speeed of Light Odd Bodkin <bodkinodd@gmail.com> - 2018-04-09 19:34 +0000
      Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-04-09 21:10 -0500
        Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-10 17:56 +0100
          Re: The Speeed of Light Odd Bodkin <bodkinodd@gmail.com> - 2018-04-10 18:39 +0000
          Re: The Speeed of Light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-04-10 20:40 +0200
          Re: The Speeed of Light Lofty Goat <rlwatkins@gmail.com> - 2018-04-10 14:23 -0500
            LET EXPERIMENT DECIDE ('cos i think Relativists are Charlatans eh!) Keith Stein <keithstein111@gmail.com> - 2018-04-10 21:28 +0100
          Re: The Speeed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-04-14 09:11 -0500
            Re: The Speeed of Light Keith Stein <keithstein111@gmail.com> - 2018-04-14 18:44 +0100
    Re: The Speeed of Light Whisper <beaver999@ozemail.com> - 2018-04-10 20:43 +1000
      Speed of light (was: The Speeed of Light) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-04-12 06:25 +0200
  Re: The Speeed of Light Edward Prochak <edprochak@gmail.com> - 2018-04-11 09:58 -0700

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