[time-nuts] Result of Earth Quake speeds up earth?

[Jim Palfreyman]

No one has commented on my graph. I would have thought that change
would easily be detected.

Jim

On Sunday, March 20, 2011, cook michael <michael.cook at sfr.fr> wrote:
> Le 20/03/2011 05:59, Bruce Griffiths a écrit :
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> jimlux wrote:
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> A 10-12m diameter dish is probably close to the minimum feasible aperture.
> A 4m dish can be made to work in conjunction with a mauch larger dish
> (eg 30m).
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> The original speculation was for measuring the small change in earth rotation rate, for which some sort of interferometric measurement of a stellar source could be used.
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> I sincerely doubt that it will be possible to get undisputed verification of this speed up as the magnitude is swamped by the irregular diurnal and sub-diurnal rotation rates induced by tidal effects that are at lease a magnitude greater and for which the error bars are of the same order or grater than the predicted shift.
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> There was a similarly predicted rotation shift predicted for the Chile quake of 28 February 2010 (1,26us). There was IIRC no verification of that AFAIK. Check the tidal effects at
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> http://bowie.gsfc.nasa.gov/ggfc/tides/intro.html  for the tidal effect
> and
> http://hpiers.obspm.fr/     for rotational measured speed changes
> http://hpiers.obspm.fr/eop-pc/index.php?index=news    for the statement of detectability.
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> The source has to be bright (so you can detect it with a practical antenna.. not everyone has a 30m dish in their back yard)
> The source has to be small angle (or at least something that you could accurately determine the centroid of)
> The source has to be "not moving"  (which I think leaves out using something like jupiter)
> The frequency of measurement has to be somewhere that the atmosphere won't dominate the uncertainty (leaving out optical, I think)
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> SO what's the brightest small angular radio source out there?
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> 3C273
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> RA 12:29.1 DEC 02:03.1
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> As someone else has pointed out, measuring the earth surface position relative to spacecraft orbits, e.g. GPS, would be another technique.  In fact, a high resolution measurement of the position of a geosync sat might do.. If the earth's rotation rate changes you'd have to adjust the height of the satellites in Clarke orbit to keep them stationary.
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> Unfortunately, for earth orbiters, there's enough other perturbations that you probably can't see it.  They already have to move satellites around to compensate for things like solar wind, air drag (for LEO), etc.
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> But maybe for a spacecraft in deep space, between planets, which is on a well understood trajectory?
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> Bruce
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