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View Full Version : Gravity Probe B Will Tell Us If Einstein Was Right



Fraser
2005-Nov-17, 04:40 PM
SUMMARY: NASA/Stanford's Gravity Probe B spacecraft recently wrapped up a year of gathering data about the Earth's gravity field. If Einstein was correct, the Earth's rotation should twist up our planet's gravity field like a vortex. Scientists at NASA and Stanford are now analyzing the mountains of data sent back by the spacecraft to detect any shift in its orientation, which would indicate this vortex of gravity.

View full article (http://www.universetoday.com/am/publish/space-time_vortex_gpb.html)
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Don Alexander
2005-Nov-17, 09:02 PM
For many people, a dream has come true. GP-B has been the space probe with the longest history ever, the first concept dating back to 1959. No matter what will finally be found, the engineering success is an absolute marvel.

See you on the cover of Science or Nature!!

D. A. Kann
PhD student, Gamma-Ray Burst Afterglow Collaboration at ESO
Thueringer Landessternwarte Tautenburg, Germany

Metricyard
2005-Nov-17, 11:01 PM
Gravity Probe-B was truely and engineering feat.

I've been following its progress for quite awhile. Can't believe it took so many decades to get this thing off the ground.

I'm just glad that the main scientists got to see the probe complete its mission in their lifetimes.

GBendt
2005-Nov-18, 12:11 AM
Hi,

The idea was simple, but to make its item a reality was extremely difficult.
It took its time to develop the method to produce the main elements of the gravity sensor: Spheres of silicon which are accurate spheres, with a deviation of the actual sphere surface shape from the exact shape of the ideal sphere being less than a layer of 10 silicon atoms.
Nothing as precisely manufactured was ever produced by any technology.

Regards,

GŁnther

Fortunate
2005-Nov-18, 01:11 AM
It wil be interesting to see how the magnitude of the result compares with the magnitude of the experimental uncertainty. I am very excited about this.

Will GPB continue to send back data - so that the gyroscopic displacement might become larger and larger as time passes?

Gsquare
2005-Nov-18, 02:47 AM
SUMMARY: NASA/Stanford's Gravity Probe B spacecraft ....

[time_vortex_gpb.html]View full article[/URL]
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There is also a Gen Rel. geodetic deflection being measured besides the deflection due to the gravitomagnetism mentioned in the article.

Interestingly, it did refer indirectly to the unique detection (spin readout) technique based on a not too commonly known effect of a rotating superconductor.

Gsquare

--Eat right, stay fit, die anyway.--

ChrisColes
2005-Nov-18, 10:26 AM
Open message to Fraser,

I believe that the probe will find that instead of the vortice being as illustrated sitting under the pole, (as though the Earth is sitting within a bowl), it will show that there are a number of vortices inter-related with the related position of the Sun and the planets. That there are vortice attachments to the Sun and the planets. These vortices will reflect direct gravitational attachment, via a vortex, to the Sun and anything else of sufficient mass that surrounds the Earth. Thus these vortices will move upon the surface of Earth in direct relationship to the relative positions of the surrounding mass objects, the primary one being the Sun.

The vortices are caused, not by a sort of space time distortion, but by the gravitational attachment of all the mass objects through gas molecules that are unable to detach , either from each other nor from the mass objects.

Just like wing tip vortices.

Chris Coles.

Gsquare
2005-Nov-18, 02:32 PM
....... Scientists at NASA and Stanford are now analyzing the mountains of data sent back by the spacecraft to detect any shift in its orientation, which would indicate this vortex of gravity.

View full article (http://www.universetoday.com/am/publish/space-time_vortex_gpb.html)
What do you think about this story? .

That was going to be my other comment.
I am totally against using the term 'vortex'. Its the first time I've ever heard the term used in context of the earth's gravitomagnetic field, and as you can see, it leaves the door open for all types of misconceptions and misrepresentations as to the true nature of the effect.

The earth's gravitomagnetic (Lense-Thirring) field, as predictedby general relativity, is due to the rotation of earth's mass, and is a dipolar field orienting itself around the earth similar to the orientation of the earth's magnetic field.
It's orientation is only somewhat similar - It orients around the rotation axis of the earth (whereas the magnetic field is somewhat off axis). Calling it a vortex simply because of a preconception of how space-time is affected appears to me to be misleading and leads to all sorts of false conceptions, especially when considering the extremely tiny magnitude of the effect.

G^2

Dark Jaguar
2005-Nov-23, 10:10 PM
Oh wow, yeah the word "vortex" will be added to the official crazy people lexicon...