| Topic: |
Science > Physics |
| User: |
"Sam Wormley" |
| Date: |
18 Jun 2007 07:30:55 PM |
| Object: |
Gravity Probe-B Status June-August 2007 Part I |
Gravity Probe-B Status June-August 2007 Part I
http://www.spaceref.com/news/viewsr.html?pid=24566
STATUS REPORT
Date Released: Monday, June 18, 2007
Source: Stanford University
Note: This GP-B update is essentially a revised and expanded version
of the GP-B press release that we posted in April that tells a more
readable and complete story about the goals of GP-B, what we've
accomplished to date, the surprises we've encountered and how we're
addressing them, and the steps we are taking towards a final results
announcement at the end of the year.
This story is too long for a single email message, so I've divided it
into two parts. Part I below contains the main story. Part II, which
will arrive today in a separate email, contains a more detailed
description of the two surprises we encountered (time-varying polhode
paths of the gyros and misalignment torques on the gyros) and their
underlying cause (electrostatic patches on the gyro rotors and
housings). The Web version of these stories at
http://einstein.stanford.edu is fully illustrated with graphs,
drawings, photos, and even a couple of Flash animations. In addition,
we now have a special Web page devoted to our announcement and
presentations at the April 2007 meeting of the American Physical
Society (APS), including MP3 audio recordings and PDF copies of the
presentation slides at
http://einstein.stanford.edu/content/aps_posters.
Our next regularly scheduled mission update will be towards the end
of August. Until then, we hope you have a good summer.
Bob Kahn
GP-B Public Affairs
GP-B SUCCEEDED IN COLLECTING THE DATA TO TEST EINSTEIN'S PREDICTIONS
ABOUT GRAVITY
Over four decades of planning, inventing, designing, developing,
testing, training and rehearsing paid off handsomely for GP-B. The
17.3-month flight mission succeeded in collecting all the data needed
to carry out this unprecedented, direct experimental test of
Einstein's general theory of relativity-his theory of gravity.
GP-B is arguably the most sophisticated spacecraft ever flown. It
incorporated many new technologies-most notably the gyros, their
suspension systems, the accompanying SQUID readouts, and the
precision-pointing of the spacecraft-fixed telescope-all of whose
debut performances in space occurred during this mission. It is
remarkable, and a testament to the preparation, talent, knowledge and
skill of the Stanford-NASA-Lockheed Martin development team, that all
of these technologies performed exceedingly well on orbit, with some,
such as the Gyro Suspension System and SQUID readouts, significantly
exceeding their required performance specifications.
As Gaylord Green, the GP-B Program Manager during launch operations,
remarked after the spacecraft was in orbit and all systems were
functioning nominally: "...10,000 things went right!"
--> View a 2-page overview of GP-B in a nutshell at:
http://einstein.stanford.edu/content/fact_sheet/GP-B_Nutshell-0307.pdf
--> View a 28-page summary of the GP-B program, including its
history, experimental design, technology, mission and legacy at:
http://einstein.stanford.edu/content/exec_summary/GP-B_ExecSum-scrn.pdf
THE EFFECTS OF GENERAL RELATIVITY ARE CLEARLY VISIBLE
The GP-B satellite was designed as a pristine, space-borne
laboratory, whose primary task was to use four ultra-precise
gyroscopes to measure directly two effects predicted by general
relativity. One is the geodetic effect-the amount by which the mass
of the Earth warps the local space-time in which it resides. The
second effect, called frame-dragging, is the amount by which the
rotating Earth drags local space-time around with it. Because the
spacecraft is in a polar orbit, the two effects occur at right angles
to each other, giving a clean separation between them. Furthermore,
the gyros are arranged such that each measures both effects.
According to Einstein's theory, over the course of a year, the
geodetic warping of Earth's local space-time should cause the spin
axis of each gyroscope to shift from its initial alignment by a
minuscule angle of 6.606 arc-seconds (0.0018 degrees) in the plane of
the spacecraft's orbit. Likewise, the twisting of Earth's local
space-time should cause the spin axis to shift by an even smaller
angle of 0.039 arc-seconds (0.000011 degrees)-about the width of a
human hair viewed from a quarter mile away-in the plane of the
Earth's equator.
In the plot shown on our Web site,
(http://einstein.stanford.edu/highlights/gyro_drift_plots_fe.jpg) the
geodetic effect is clearly visible in the unprocessed data from the
GP-B gyroscopes, confirming Einstein's predictions to a precision of
better than 1 percent. As Professor Francis Everitt, GP-B Principal
Investigator, recently remarked: "It's fascinating to be able to
watch the Einstein warping of spacetime directly in the tilting of
these GP-B gyroscopes-more than a million times better than the best
inertial navigation gyroscopes."
We have also seen indications of the frame-dragging effect, which is
170 times smaller than the geodetic effect. GP-B scientists are still
in the process of extracting its signature from the spacecraft data.
FIRST PEEK AT RESULTS PRESENTED AT APRIL APS MEETING; FINAL RESULTS
IN DECEMBER
After 18 months of rigorous, ground-breaking data analysis, our
science team presented the first public peek at the results
summarized above during the April meeting of the American Physical
Society (APS) in Jacksonville, Florida. Professor Francis Everitt
kicked off the April APS meeting with a plenary talk entitled:
Gravity Probe B Interim Report and First Results. In addition,
various GP-B team members gave three invited talks, two submitted
papers and presented 22 poster papers on various aspects of GP-B.
The preliminary results we announced at the April APS meeting for the
geodetic effect are consistent with the prediction of general
relativity to an accuracy of ~1.0 percent. This is on par with the
only other measurement of this effect that was performed using the
Earth-Moon system orbiting the Sun, but seen in a different and much
more direct way. Moreover, the indications of frame-dragging measured
thus far are also highly encouraging. However, for both measurements,
the current level of experimental error must be significantly reduced
and the measurements thoroughly cross-checked before being announced
as final results.
The inherent noise in the GP-B SQUID readout system imposes a natural
physical limitation on the experimental accuracy that it is possible
to achieve with the GP-B instrument. For the geodetic effect, this
limit is ~0.01 percent, and for the much smaller frame-dragging
effect, the limit is ~1.0 percent. The goal of GP-B is to achieve the
highest possible experimental accuracy, approaching the physical
limitations of the instrument readout.
The GP-B science instrument has sufficient resolution and we have
collected ample data to obtain results approaching these limits.
However, early in the data analysis, our science team uncovered
surprising torque and sensor effects (from polhode motion of the
gyros) that must separated and removed from the relativity effects in
order to obtain the desired level of accuracy. Addressing these
torque and sensor effects has been our science team's dominant focus
in recent months, and this has led to a longer and more sophisticated
data analysis process than was originally anticipated.
Three weeks prior to the APS meeting, our GP-B science team reviewed
the progress with the independent GP-B Science Advisory Committee
(SAC) that has been consulting with us on every aspect of the program
for the past decade. Summarizing the committee's findings and
recommendations, SAC Chairman, Professor Clifford Will of Washington
University in St. Louis, MO. and author of the classic text, Theory &
Experiment in Gravitational Physics, reported: "The GP-B science team
is continuing to make good progress on a number of fronts... We
strongly support the [Stanford] proposal for funding through December
2007 to complete the data analysis and prepare publication of the
final GP-B result." NASA has committed to extending support for GP-B
at the required level.
At the APS meeting, GP-B Program Manager, William Bencze, summarized
the situation: "Understanding the details of this science data is a
bit like an archeological dig: a scientist starts with a bulldozer,
follows with a shovel, and then he finally uses dental picks and
toothbrushes to clear the dust away from the treasure. We are passing
out the toothbrushes now."
--> View details about the GP-B presentations at the April APS
meeting, including PDF presentation slides and corresponding MP3
audio recordings of all the talks and reduced-size PDF copies of all
the posters at: http://einstein.stanford.edu/content/aps_posters
THE TWO SURPRISES & THEIR IMPACT ON THE EXPERIMENT
Francis Everitt is fond of telling the story that in the months
leading up to the GP-B launch, several people who had deep experience
with other space missions told him that all the things he knew were
likely to go wrong would work perfectly, but other things that
couldn't possibly cause any difficulty would keep the team up at
night.
These turned out to be prophetic words. Our science team made two
significant discoveries about the science instrument that have
lengthened the data analysis process:
1. Shortly after the gyros were spun up in August 2004, we discovered
that the polhode motion of the gyro rotors, which was expected to
exhibit a constant pattern throughout the experimental period, was
changing over time, significantly complicating the calibration of the
gyroscope readout angles.
2. During the post-experiment instrument calibration testing in
August-September 2005, the spin axes of the gyroscopes were found to
be affected by certain class of small classical torques, known as
"misalignment torques," whose effects must be rigorously separated
from the relativity measurements.
However, the team was prepared for such an eventuality. In fact, the
GP-B experiment was carefully designed to enable us to discover such
unexpected sources of error. As Francis Everitt notes: "When trying
to do an experiment that goes seven orders of magnitude beyond where
anyone has gone before, some extraordinary planning is necessary.
First, you design the experiment to make all the errors as close to
zero as possible. Next, you average everything you can-for example,
you roll the spacecraft throughout the experiment. Finally, you
purposely look for things that were not expected."
During one of many NASA program reviews prior to launch, experienced
investigators from other NASA missions asked us what processes we had
put in place to discover systematic sources of error that might crop
up in the data. Our answer was that we would follow a principle set
forth by the 18th century scientist, Henry Cavendish-namely, if you
are worried that something in an experiment might be a potential
source of error, you take the step of deliberately exaggerating the
error sources to determine how bad they can get. This process enables
you to quantify the magnitude of the problem and determine a way to
deal with it.
From mid-August through September 2005, after collecting 50 weeks of
science data and before the liquid helium was exhausted from the
dewar, we followed Cavendish's principle by performing a barrage of
calibration tests on all parts of our science instrument. These
tests, along with other tests that we performed throughout the
mission, enabled us to confirm that all of the known and expected
sources of error-with one exception-were, in fact, negligible as
expected. As William Bencze put it: "Without the extensive
calibration tests, we would have been looking for a needle in a
haystack; instead, we only had to look for a needle on the floor."
Specifically, these tests confirmed that six of the seven extrinsic
"near zero" design specifications of the experiment
(http://einstein.stanford.edu/content/exec_summary/GP-B_ExecSum-scrn.pdf#page=9)
had been met or exceeded, and we were able to eliminate each of these
factors as sources of error in the final results. The exception that
we could not eliminate as a source of error was the seventh extrinsic
design constraint that the electric dipole moment of the gyro rotors
be "near zero." In other words, the gyro rotors must be highly
electrically spherical as well as mechanically spherical.
The electrical out-of-roundness is due to larger than anticipated
electrostatic patches (regions of electrical charge) on the rotor's
surface. These patches interact with similar ones on the housing's
inner surface to give rise to small "misalignment torques" that occur
when the spin axes of the gyros are not aligned with the roll axis of
the spacecraft. These patches also provide a subtle damping mechanism
that extracts small amounts of energy from the spinning rotor, and
this causes the polhode path to change. The potential existence of
these patches was known prior to launch, but was believed to be
negligible, based on careful physical analysis and laboratory
measurements.
Nature is full of surprises, and it is common for physics
experiments, particularly a ground-breaking experiment such as GP-B,
to uncover unexpected phenomena. Because we anticipated this
situation and were actively looking for surprises in the data, we
were prepared to deal with them. Consequently, the team has been able
to model precisely the polhode motion of all four gyroscopes, as well
as the classical torques imparted by patch effects on the rotors and
housings. This painstaking work, which is still in progress, has
lengthened the data analysis phase of the mission by more than a
year-such is the nature of scientific inquiry. Ultimately, the time
spent isolating and removing these confounding effects from the final
results will reduce the current margin of experimental error to the
desired level.
Our goal in GP-B has always been to perform the best possible
experiment and to use great care and redundancy to ensure the
validity of the results. Every experiment has its share of unknowns
or challenges that no one could have anticipated. But once such
challenges surface, it is incumbent on the investigators to spend
time addressing them and accounting for them in the process of
determining the final outcome.
--> View a PDF copy of Professor Francis Everitt's 1977 paper
entitled: Gravitation, Relativity and Precise Experimentation, which
describes Henry Cavendish's torsion balance experiments to determine
the value of the gravitational constant, G, as well as other
high-precision experiments at:
http://einstein.stanford.edu/content/sci_papers/papers/Everitt_Gravitation-Precise-Expt-1977.pdf
--> Read a more detailed description of the GP-B gyro polhode motion,
misalignment torques, and patch effects in Part II of this update,
which will be sent as a separate email.
NEXT STEPS-MOVING TOWARDS A FINAL RESULT
Last summer (2006), GP-B chief scientist, Mac Keiser, devised a
clever geometric approach for separating the disturbance
(misalignment) torques from the relativity signals. Over the past
year, we have been pursuing a combination of Keiser's geometric
approach along with more traditional algebraic, model-based
estimation approaches. Recently, we have found a way to combine
aspects of both the geometric and algebraic approaches into a unified
data analysis process, and we will be continuing to employ this
unified approach through the end of the analysis.
Specifically, our science team is focusing on two main issues:
1. Fine calibration of the gyroscope/telescope scale factor
Both the SQUID-based magnetic measurement of the gyro spin axes and
the telescope measurement of the spacecraft pointing direction with
respect to the guide star produce electrical signals that represent
angular measurements. Because these two systems are independent of
each other, it is necessary to cross-calibrate these instruments to
ensure that both systems are measuring the same relative angle when
the orientation of the spacecraft changes.
Because of trapped magnetic flux on the gyro rotors, the
calibration-conversion from electrical signals to angles-of the gyro
readout can vary in a complex, but computable way. Specifically, it
is affected by the polhode period of the gyros, which was found to
change during the flight mission, rather than remaining constant as
originally expected.
To address these issues and determine the correct scale factor, the
team is in the process of precisely modeling the time-varying polhode
periods of each gyro for each orbit as well as creating precise
mappings of the trapped magnetic flux on the surface of each gyro
rotor.
2. Refining the analysis of the misalignment torques The team is in
the process of refining the data analysis techniques being used to
separate and remove these classical misalignment torques from the
relativity effects. To do this, it is necessary to take into account
many variables, including vehicle motion and polhode paths of the
gyros.
The refinement of the misalignment torques and the mapping of the
trapped magnetic flux on the gyro rotors interact such that if one is
incorrect, the other becomes harder. There is also a symbiotic
relationship between these two activities so that as one improves, it
facilitates calculating the other.
In addition to these two activities, the GP-B guide star (IM Pegasi)
proper motion data is being held by Irwin Shapiro and his group at
the Harvard Smithsonian Center for Astrophysics (CfA). Upon
completion of the data analysis endeavor here at Stanford, this
extremely precise VLBI measurement data will be substituted for the
current placeholder values for the proper motion of IM Pegasi, taken
from the 1997 Hipparcos [star] Catalogue, in order to obtain the
greatest possible accuracy in the final GP-B result.
--> View our APS Meeting page, where you can download an audio
recording and PDF slides from Irwin Shapiro's APS paper, plus two
poster papers on the GP-B Guide Star Astrometry Project at the CfA
at: http://einstein.stanford.edu/content/aps_posters/index.html#talks
OTHER MISSION NEWS
GP-B DATA ARCHIVE TO BE AVAILABLE THROUGH NSSDC IN JULY
During the past few weeks, while our science team continues to
analyze the data, our GP-B data processing team has also been quite
busy, compiling an archive of the GP-B raw dataoboth science data and
spacecraft/payload status data, as well as an archive of associated
documents, drawings, photos and other information about the GP-B
mission. We are currently in the process of transferring this entire
archive to the National Space Science Data Center (NSSDC), located at
the NASA Goddard Space Flight Center in Greenbelt, Maryland. Transfer
of this archive will be completed in late June, and the GP-B archive
will then become publicly available sometime thereafter.
ASTRONOMER SPOSETTI NAMES 3 MINOR PLANETS HONORING GP-B PRINCIPALS
Swiss physics teacher and amateur astronomer Stefano Sposetti, along
with his colleagues and pupils, has been following GP-B with great
interest for a number of years. In August 2004, he photographed the
GP-B spacecraft in orbit through his telescope as it passed through
the constellation Pegasus, the location of our GP-B guide star, IM
Pegasi (see our Mission Update of 13 August 2004 at:
http://einstein.stanford.edu/highlights/hl_081304.html#sposetti
Recently, Mr. Stefano sent us an email message noting that last year
he sent proposals to the Minor Planet Center (MPC) for naming three
minor planets he had discovered in 2000 to honor some of the people
involved in the GP-B experiment. The MPC has officially accepted his
proposals and now three GP-B principals--Leonard Schiff, Francis
Everitt, and William Fairbank--have joined the long list of minor
planet names.
-->Read more about the three minor planets that Mr. Sposetti
discovered and view simulations of their orbits at:
http://einstein.stanford.edu/highlights/hl_sposetti_mpo.html.
We very much appreciate Mr. Sposetti's long-standing interest in GP-B
and we are grateful to him for sending us this information.
NEXT SCHEDULED GP-B UPDATE AT THE END OF AUGUST 2007
Our next regularly scheduled update will be towards the end of
August. Of course, we will send out a timely update if noteworthy
events occur here at GP-B in the meantime.
PREVIOUS GP-B UPDATES
If you wish to read any of our previous updates, our GP-B Web site
includes a chronological archive of all the updates/highlights (with
photos and drawings) that we have posted over the past 8 years:
http://einstein.stanford.edu/highlights/hlindexmain.html
OTHER LINKS THAT MAY INTEREST YOU
* Our GP-B Web site, http://einstein.stanford.edu contains loads of
information about the Gravity Probe B experiment, general relativity,
and the amazing technologies that were developed to carry out this
experiment.
* GP-B Frequently Asked Questions (FAQ):
http://einstein.stanford.edu/content/faqs/faqs.html
* Video and/or audio of May 18, 2006 public lecture by Principal
Investigator, Professor Francis Everitt, on GP-B. You can view a
streaming video of the lecture in your Web browser:
http://einstein.stanford.edu/highlights/hl_video_everitt051806.html.
You can also download either a video or audio only copy of the
lecture to an iPod from the Stanford University iTunes U Web site:
http://itunes.stanford.edu, This Web page automatically launches the
Apple iTunes program on both Macintosh and Windows computers, with a
special Stanford on iTunes U "music store," containing free downloads
of Stanford lectures, performances, and events. Francis Everitt's
"Testing Einstein in Space" lecture is located in the Faculty
Lectures section. People with audio-only iPods can download the
version under the Audio tab; people with 5th generation (video)
iPodfs can download the version under the Video tab.
* Visual tour of the GP-B spacecraft and payload from our GP-B Web
site: http://einstein.stanford.edu/content/vehicle_tour/index.html
* PDF file containing a 1/20 scale, paper model of the GP-B
spacecraft that you can download print out, and assemble:
http://einstein.stanford.edu/content/paper_model.
* NASA's Marshall Space Flight Center also has a series of Web pages
devoted to GP-B: http://www.gravityprobeb.com
* The Harvard-Smithsonian Center for Astrophysics (Cambridge) and
York University (Toronto), with contributions from the Observatoire
de Paris, have been studying the motions of the guide star, IM Pegasi
for over a decade. To find out more, visit:
http://www.yorku.ca/bartel/guidestar/
* In addition, you'll find information in the Guide Star FAQ on our
Web site:
http://einstein.stanford.edu/content/faqs/faqs.html#guidestar and on
pages 18-20 of the Gravity Probe B Launch Companion:
http://einstein.stanford.edu/highlights/GP-B_Launch_Companion.pdf
* The Einstein Exhibition at the Skirball Cultural Center in Los
Angeles has closed.However, you can visit the American Museum of
Natural History's virtual Einstein exhibit on the Web at:
http://www.skirball.org/exhibit/amnh_frame.html
.
|
|
| User: "Tom Potter" |
|
| Title: Potter status report on Gravity Probe B |
19 Jun 2007 05:13:09 AM |
|
|
"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:3tFdi.109614$n_.73392@attbi_s21...
Gravity Probe-B Status June-August 2007 Part I
http://www.spaceref.com/news/viewsr.html?pid=24566
STATUS REPORT
Date Released: Monday, June 18, 2007
Source: Stanford University
Note: This GP-B update is essentially a revised and expanded version
of the GP-B press release that we posted in April that tells a more
readable and complete story about the goals of GP-B, what we've
accomplished to date, the surprises we've encountered and how we're
addressing them, and the steps we are taking towards a final results
announcement at the end of the year.
http://einstein.stanford.edu/
"SAC Chairman, Professor Clifford Will of Washington University in St.
Louis, MO. author of the classic text, Theory & Experiment in
Gravitational
Physics, reported: "We strongly support the [Stanford] proposal
for funding through December 2007.."
Potter observation:
=============
It seems to me that the smartest thing that the General Relativity
Gurus
at Stanford and Washington University could do,
would be to use their powerful, esoteric knowledge of reality in the
free
market, and make billions of dollars,
rather than beg the taxpayers for billions of more dollars.
http://einstein.stanford.edu/
"Over four decades of planning, inventing, designing, developing,
testing,
training and rehearsing paid off handsomely for GP-B.
The 17.3-month flight mission succeeded in collecting all the data
needed
to carry out this unprecedented, direct experimental test of
Einstein's
general theory of relativity
-his theory of gravity. "
"Consequently, the team has been able to model precisely the polhode
motion
of all four gyroscopes, as well as the classical torques
imparted by patch effects on the rotors and housings.
This painstaking work, which is still in progress,
has lengthened the data analysis phase of the mission by more than a
year
-such is the nature of scientific inquiry.
Ultimately, the time spent isolating and removing these confounding
effects
from the final results will reduce the current margin of experimental
error
to the desired level.
Potter translation:
============
"After 40 years of planning,
and 17.3 months of taking data,
and two years of hacking the data,
we had to take another year,
a few million more of the taxpayer's dollars
and a number of Classical Physics hacks of the data,
in order to fit the data to the General Relativity model
to the desired level,
and as we don't have a bulletproof case,
we need another year or so of taxpayer funding."
Potter editorial comment:
=================
The Scatterometer (QuickScat) satellite
that uses radar to measures near-surface wind speed and direction
under all weather and cloud conditions over Earth's oceans
suffered the failure of a transmitter and
is now operating on a backup transmitter.
A replacement satellite was supposed to be built in 2008,
but Congress pushed the project back to 2016
because of the cost of Bush's War against the Iraqi people,
and satellite projects like Gravity Probe B.
No doubt Gravity Probe B is useful if one wants to rationalize
General Relativity for national, racial or religious glorification,
or speculate about the beginning and end of the universe,
black holes, worm holes, and time travel,
but it seems to me, that preventing
the loss of lives, and billion dollar infrastructure losses,
such as occurred in New Orleans,
should take precedence over rationalizing a non-viable model of
reality,
that generates more heat than light.
--
Tom Potter
*** Time Magazine Person of the Year 2006 ***
*** May 2007 Anti-Bigot Award ***
http://home.earthlink.net/~tdp
http://tdp1001.googlepages.com/home
http://no-turtles.com
http://www.frappr.com/tompotter
http://photos.yahoo.com/tdp1001
http://spaces.msn.com/tdp1001
http://www.flickr.com/photos/tom-potter
http://tom-potter.blogspot.com
.
|
|
|
|
| User: "Tom Potter" |
|
| Title: Potter status report on Gravity Probe-B |
19 Jun 2007 01:44:35 AM |
|
|
"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:3tFdi.109614$n_.73392@attbi_s21...
Gravity Probe-B Status June-August 2007 Part I
http://www.spaceref.com/news/viewsr.html?pid=24566
STATUS REPORT
Date Released: Monday, June 18, 2007
Source: Stanford University
Note: This GP-B update is essentially a revised and expanded version
of the GP-B press release that we posted in April that tells a more
readable and complete story about the goals of GP-B, what we've
accomplished to date, the surprises we've encountered and how we're
addressing them, and the steps we are taking towards a final results
announcement at the end of the year.
http://einstein.stanford.edu/
"SAC Chairman, Professor Clifford Will of Washington University in St.
Louis, MO. author of the classic text, Theory & Experiment in Gravitational
Physics,
reported: "We strongly support the [Stanford] proposal
for funding through December 2007.."
Potter observation:
=============
It seems to me that the smartest thing that the General Relativity Gurus
at Stanford and Washington University could do,
would be to use their powerful, esoteric knowledge of reality in the free
market, and make billions of dollars,
rather than beg the taxpayers for billions of more dollars.
http://einstein.stanford.edu/
"Over four decades of planning, inventing, designing, developing, testing,
training and rehearsing paid off handsomely for GP-B.
The 17.3-month flight mission succeeded in collecting all the data needed
to carry out this unprecedented, direct experimental test of Einstein's
general theory of relativity
-his theory of gravity. "
"Consequently, the team has been able to model precisely the polhode motion
of all four gyroscopes, as well as the classical torques
imparted by patch effects on the rotors and housings.
This painstaking work, which is still in progress,
has lengthened the data analysis phase of the mission by more than a year
-such is the nature of scientific inquiry.
Ultimately, the time spent isolating and removing these confounding effects
from the final results will reduce the current margin of experimental error
to the desired level.
Potter translation:
============
"After 40 years of planning,
and 17.3 months of taking data,
and two years of hacking the data,
we had to take another year,
a few million more of the taxpayer's dollars
and a number of Classical Physics hacks of the data,
in order to fit the data to the General Relativity model
to the desired level,
and as we don't have a bulletproof case,
we need another year or so of taxpayer funding."
Potter editorial comment:
=================
The Scatterometer (QuickScat) satellite
that uses radar to measures near-surface wind speed and direction
under all weather and cloud conditions over Earth's oceans
suffered the failure of a transmitter and
is now operating on a backup transmitter.
A replacement satellite was supposed to be built in 2008,
but Congress pushed the project back to 2016
because of the cost of Bush's War against the Iraqi people,
and satellite projects like Gravity Probe B.
No doubt Gravity Probe B is useful if one wants to rationalize
General Relativity for national, racial or religious glorification,
or speculate about the beginning and end of the universe,
black holes, worm holes, and time travel,
but it seems to me, that preventing
the loss of lives, and billion dollar infrastructure losses,
such as occurred in New Orleans,
should take precedence over rationalizing a non-viable model of reality,
that generates more heat than light.
--
Tom Potter
*** Time Magazine Person of the Year 2006 ***
*** May 2007 Anti-Bigot Award ***
http://home.earthlink.net/~tdp
http://tdp1001.googlepages.com/home
http://no-turtles.com
http://www.frappr.com/tompotter
http://photos.yahoo.com/tdp1001
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| User: "Jan Panteltje" |
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| Title: Re: Gravity Probe-B Status June-August 2007 Part I |
19 Jun 2007 04:09:46 AM |
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On a sunny day (Tue, 19 Jun 2007 00:30:55 GMT) it happened Sam Wormley
<swormley1@mchsi.com> wrote in <3tFdi.109614$n_.73392@attbi_s21>:
Still no results.
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