View Full Version : Gravity Probe B bored of normal life
Italo Vecchi
Dec14-04, 10:18 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\n\nBob Kahn writes in his " Gravity Probe B Update -- December 10, 2004 ([1])\n\n"At 1:48PM, Pacific Time, an odd event silently occurred on-board the\nspacecraft, ... , An assessment of the safemodes that\nwere triggered indicated that an error-never seen before had\noccurred in a module of the Attitude and Translation Control (ATC)\ncomputer system. The spacecraft\'s GPS had registered an off-the-scale\nvelocity spike, which if correct, indicated that, for one brief\nmoment, the spacecraft had traveled faster than the speed of light-or\nto use Star Trek terminology, it had "warped into hyperspace. ...\nthis anomaly was apparently caused by one of the four accessible GPS\nsatellites being in the wrong position for proper GPS triangulation.\nThe ATC system usually catches situations of this kind and disallows\nthe data; but, this one slipped through the filter. ...\nThe fact that an anomalous event occurred while the spacecraft was flying\nthrough the SAA region appears to be a coincidence-or is it?"\n\nAnyone commenting on this?\n\nIV\n\n[1] http://einstein.stanford.edu/highlights/hlindexmain.html\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>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
Dec15-04, 12:38 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Italo Vecchi wrote:\n>\n> Bob Kahn writes in his " Gravity Probe B Update -- December 10, 2004 ([1])\n>\n> "At 1:48PM, Pacific Time, an odd event silently occurred on-board the\n> spacecraft, ... , An assessment of the safemodes that\n> were triggered indicated that an error-never seen before had\n> occurred in a module of the Attitude and Translation Control (ATC)\n> computer system. The spacecraft\'s GPS had registered an off-the-scale\n> velocity spike, which if correct, indicated that, for one brief\n> moment, the spacecraft had traveled faster than the speed of light-or\n> to use Star Trek terminology, it had "warped into hyperspace. ...\n> this anomaly was apparently caused by one of the four accessible GPS\n> satellites being in the wrong position for proper GPS triangulation.\n> The ATC system usually catches situations of this kind and disallows\n> the data; but, this one slipped through the filter. ...\n> The fact that an anomalous event occurred while the spacecraft was flying\n> through the SAA region appears to be a coincidence-or is it?"\n>\n> Anyone commenting on this?\n>\n> IV\n>\n> [1] http://einstein.stanford.edu/highlights/hlindexmain.html\n\nSounds like Gravity B hit an SAA speed bump:\n\n"The LDX is essentially a miniature magnetosphere -- the magnetic field\nsurrounding the Earth that shields the planet from a steady bombardment\nof plasma (high-energy, ionized atoms) streaming from the sun. This\nfield traps the sun\'s plasma, protecting the atmosphere and life on the\nsurface. Other planets, like Jupiter, have much stronger magnetic\nfields while others, like Venus, have none at all.\n...\nThe idea for the experiment came from scientist Akira Hasegawa, who\nstudied plasma surrounding planets, Mauel said. In the 1980s, Hasegawa\nobserved an encounter of the Voyager spacecraft with the outer planets.\nHe noticed how effective the magnetic pressures of these planets were\nat confining plasma. Hasegawa then came up with the idea of replicating\na magnetosphere in a lab setting to confine plasma, Mauel said."\n\nhttp://www.wired.com/news/technology/0,1282,66000,00.html?tw=wn_tophead_1\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>Italo Vecchi wrote:
>
> 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
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
Dec16-04, 08:09 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>"ca314159" <ca314159@bestweb.net> wrote in message\nnews:41C0489A.9B5C4097@bestweb.net...\n.. ...\n> Sounds like Gravity B hit an SAA speed bump:\n>\n> http://www.wired.com/news/technology/0,1282,66000,00.html?tw=wn_tophead_1\n.....\n\nTha nks for the really cool pointer.\nI suppose the SAA is a household name for the Gravity Probe B team. What is\nperplexing me here is that the filter did not catch the anomaly. The\n"reasonable explanation" in Bob Kahn\'s message points to a major malfunction\nof the measuring apparatus, leaving no trace but incredible data. This\nsuggests a design flaw.\n\nIf Gravity Probe B\'s data crop will confirm mainstream expectations all\nthis won\'t matter. But if its data will turn out to conflict with what was\nexpected then it\'s likely that this "strange" episode will be used to\ndismiss the overall validity of the data gathering process.\n\nCheers,\n\nIV\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>"ca314159" <ca314159@bestweb.net> wrote in message
news:41C0489A.9B5C4097@bestweb.net...
.....
> Sounds like Gravity B hit an SAA speed bump:
>
> http://www.wired.com/news/technology/0,1282,66000,00.html?tw=wn_tophead_1
.....
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
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>The GPB website itself http://einstein.stanford.edu/ gives this\nexplanation\n"We initially assumed that the GPS receiver had suffered a proton hit\nin the SAA region, but further analysis suggests that this was not the\ncase. Rather, this anomaly was apparently caused by one of the four\naccessible GPS satellites being in the wrong position for proper GPS\ntriangulation. The ATC system usually catches situations of this kind\nand disallows the data; but, this one slipped through the filter. "\n\n------------------------------------------------------------------------\nThis post submitted through the LaTeX-enabled physicsforums.com\nTo view this post with LaTeX images:\nhttp://www.physicsforums.com/showthread.php?t=56718#post403576\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>The GPB website itself http://einstein.stanford.edu/ gives this
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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