[FPSPACE] Monitoring 2 NASA satellites for 11 years provesframe-dragging

Jens Kieffer-Olsen dstdba at post4.tele.dk
Mon Oct 25 03:28:02 EDT 2004


> -----Original Message-----
> From: DwayneDay [mailto:zirconic1 at earthlink.net] 
> Sent: Saturday, October 23, 2004 5:49 PM
> Subject: Re: [FPSPACE] Monitoring 2 NASA satellites for 11 
> years provesframe-dragging
> 
> -----Original Message-----
> From: Nick Watkins <nww62 at yahoo.co.uk>
> Sent: Oct 23, 2004 9:49 AM
> 
> >Was "frame-dragging" the *specific* effect GPB was designed 
> to test ? 
> 
> As I remember (I would have to look it up and I'm too lazy 
> for that), GPB was designed to test for two effects and frame 
> dragging was one of them.  The article below explains that 
> this test was conducted several years ago with a 20% error 
> rate, and was recently refined to 5-10%.  GPB should provide 
> evidence down to about 1% accuracy.
> 
> As I recounted here awhile ago, GPB was initially conceived 
> in the late 1950s by three naked professors in a Stanford 
> swimming pool.  But it was not possible technologically until 
> the 1990s.  However, the spacecraft requires extreme 
> precision and due to some screwups, it was delayed multiple 
> times, with costs rising.  It was only launched this year, 
> which is several years late.  Its critics claimed a long time 
> ago that by the time GPB was flying, they would probably 
> already have proof, and the spacecraft was therefore 
> redundant.  My own view is that we probably could have found 
> a better space science project to spend this $700 million on.

 It's irrelevant, whether evidence of frame-dragging has already
 been established. Proof requires an infinitesimal accuracy, which
 is not a realistic target. Improving accuracy to 1% may seem a
 modest achievement, but if the amount of frame-dragging measured
 turns out to differ from the theoretical value, then GPB will have
 an immense scientific impact.   

 One must assume that GPB provides the highest accuracy available
 to-day, such that the choice was not whether to cancel the project,
 but rather to postpone it until an even better accuracy than 1%
 could be obtained.

--
Jens Kieffer-Olsen
Slagelse, Denmark



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