View Full Version : Frame Dragging Confirmed?
selfAdjoint
Oct21-04, 07:41 AM
News story this morning.
http://www.msnbc.msn.com/id/6290610/.
Effect detected by observing two satellites over a long time.
Rothiemurchus
Oct21-04, 08:05 AM
How big an effect on the position of the satellites do the millions of laser pulses striking the satellites have.Presumably it is negligible.And what about any gases in the neighbourhood of the satellites - could the pulses affect them significantly?
selfAdjoint
Oct21-04, 10:06 AM
How big an effect on the position of the satellites do the millions of laser pulses striking the satellites have.Presumably it is negligible.And what about any gases in the neighbourhood of the satellites - could the pulses affect them significantly?
I presume the article in Nature will address those questions.
LastOneStanding
Oct21-04, 10:44 AM
That's got to be somewhat embarrassing for the Gravity Prove B group...having their $600 million program beaten by a couple of scientists looking at a couple of regular satellites.
pervect
Oct21-04, 12:53 PM
That's got to be somewhat embarrassing for the Gravity Prove B group...having their $600 million program beaten by a couple of scientists looking at a couple of regular satellites.
I don't think this satellite test is as nearly as accurate as the gravity probe B test will be when it's finished.
I have read it at physicsweb.org, and there says that the errors are about 10 %, and Gravity Probe B will be about 1 %
As well as being more accurate the Gravity Probe B is a different type of experiment. The LAGEOS satellites experiment is testing whether they are following GR geodesics that include a frame dragging perturbation. The GPB satellite is testing the frame dragging of a solid gyroscope. Solid gyroscopes may behave differently from gyros that consist of orbiting satellites. Whether they do or not is a matter of experimental investigation rather than theoretical prediction.
- Garth
News story this morning.
http://www.msnbc.msn.com/id/6290610/.
Effect detected by observing two satellites over a long time.
http://www.nasa.gov/vision/earth/lookingatearth/earth_drag.html
21 October NASA press release, it may provide some additional detail.
Has anyone seen the article in Nature?
a theory of how a spinning black hole produces polar jets, another frame-dragging effect
http://www.space.com/scienceastronomy/blackhole_jets_040817.html
this was linked to in the MSNBC article that selfAdjoint flagged.
Has the production of jets been discussed in some other thread. I would like to see a more detailed technical article on the same topic as these press releases. Anybody know of something online?
So has Gravity Probe B detected Frame Draging?
vBulletin® v3.8.7, Copyright ©2000-2012, vBulletin Solutions, Inc.