Gravity Probe B bored of normal life
Italo Vecchi
Bob Kahn writes in his " Gravity Probe B Update -- December 10, 2004 ([1])
"At 1:48PM, Pacific Time, an odd event silently occurred on-board the
spacecraft, ... , An assessment of the safemodes that
were triggered indicated that an error-never seen before had
occurred in a module of the Attitude and Translation Control (ATC)
computer system. The spacecraft's GPS had registered an off-the-scale
velocity spike, which if correct, indicated that, for one brief
moment, the spacecraft had traveled faster than the speed of light-or
to use Star Trek terminology, it had "warped into hyperspace. ...
this anomaly was apparently caused by one of the four accessible GPS
satellites being in the wrong position for proper GPS triangulation.
The ATC system usually catches situations of this kind and disallows
the data; but, this one slipped through the filter. ...
The fact that an anomalous event occurred while the spacecraft was flying
through the SAA region appears to be a coincidence-or is it?"
Anyone commenting on this?
IV
[1] http://einstein.stanford.edu/highlights/hlindexmain.html
ca314159
Sounds like Gravity B hit an SAA speed bump:
"The LDX is essentially a miniature magnetosphere -- the magnetic field
surrounding the Earth that shields the planet from a steady bombardment
of plasma (high-energy, ionized atoms) streaming from the sun. This
field traps the sun's plasma, protecting the atmosphere and life on the
surface. Other planets, like Jupiter, have much stronger magnetic
fields while others, like Venus, have none at all.
...
The idea for the experiment came from scientist Akira Hasegawa, who
studied plasma surrounding planets, Mauel said. In the 1980s, Hasegawa
observed an encounter of the Voyager spacecraft with the outer planets.
He noticed how effective the magnetic pressures of these planets were
at confining plasma. Hasegawa then came up with the idea of replicating
a magnetosphere in a lab setting to confine plasma, Mauel said."
http://www.wired.com/news/technology/0,1282,66000,00.html?tw=wn_tophead_1
I.Vecchi
news:41C0489A...@bestweb.net...
....
> Sounds like Gravity B hit an SAA speed bump:
>
....
Thanks for the really cool pointer.
I suppose the SAA is a household name for the Gravity Probe B team. What is
perplexing me here is that the filter did not catch the anomaly. The
"reasonable explanation" in Bob Kahn's message points to a major malfunction
of the measuring apparatus, leaving no trace but incredible data. This
suggests a design flaw.
If Gravity Probe B's data crop will confirm mainstream expectations all
this won't matter. But if its data will turn out to conflict with what was
expected then it's likely that this "strange" episode will be used to
dismiss the overall validity of the data gathering process.
Cheers,
IV
Karl Poessl
This happend already different times in this mission.
I also receive the e-mail from Bob Kann, and I got the opinion that they
speak a lot about this techical data because they still miss an analysis of
their data.
This project begun about in 1970, and after about 100 days of mission; they
collected lot of datas but they are not still able to say if they verified
GR predicted
precession or not. It seem to me that they are really slow....
K. Poessl
"Italo Vecchi" <vec...@weirdtech.com> ha scritto nel messaggio
news:61789046.04121...@posting.google.com...
Garth
explanation
"We initially assumed that the GPS receiver had suffered a proton hit
in the SAA region, but further analysis suggests that this was not the
case. Rather, this anomaly was apparently caused by one of the four
accessible GPS satellites being in the wrong position for proper GPS
triangulation. The ATC system usually catches situations of this kind
and disallows the data; but, this one slipped through the filter. "
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