The Pioneer Anomaly |
The Pioneer Anomaly |
Aug 20 2007, 03:33 PM
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#226
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Newbie Group: Members Posts: 5 Joined: 7-August 07 Member No.: 3115 |
There were several structural problems with the Deen report, three equations did not display and the references were missing. The author has made his report available in pdf form and it includes all of the material.
http://www.glendeen.com/npa2007/Deen_2007_..._10_Anomaly.pdf The primary reference [1] is available at arxiv.org and it is the 2005 revision. It is a 1.5 mb file. http://arxiv.org/PS_cache/gr-qc/pdf/0104/0104064v5.pdf |
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Nov 22 2007, 03:04 PM
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#227
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Member Group: Members Posts: 204 Joined: 29-June 05 Member No.: 421 |
I just noticed the team working on data recovery put out a new update:
"Pioneer Anomaly: Evaluating Newly Recovered Data". They still aren't quite to the point of having a calibrated unified dataset -- by the end of the year, they say. It does sound like their heat modeling project is going pretty well. I'm really hopeful that they will be able to conclusively answer whether or not thermal forces can explain the anomaly. |
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Jan 29 2008, 08:45 PM
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#228
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Member Group: Members Posts: 105 Joined: 13-July 05 From: The Hague, NL Member No.: 434 |
Catching up on reading ESO Messenger reports I came across an article in the June 07 edition (#128) in which Newton's law was tested in the low acceleration regime (outer regions-) of globular clusters. The rather astounding conclusion was that globular clusters behave like galaxies in that the velocity pattern in these outer regions flattens off in exactly the same pattern as measured for galaxies.
For this behaviour around galaxies it is widely assumed that large quantities of dark matter (hidden in the galaxies) are responsible. But for globular clusters this explanation is apparently not valid at all. Ergo, it seems that one of the main reasons for "inventing" dark matter in large scale gravity puzzles is no longer valid and that alternatives such as MOND gain a lot of credibility. Especially since it is "unpalatable" as the authors decribe it to assume that dark matter also is a pervasive factor in globular clusters. If someone could explain that to me that would be highly appreciated, but I take the word of the authors until advised otherwise. A modified Newton law would also go a long way in describing the Pioneer anomaly I believe. This thread will probably remain open for quite some time to come. (Pls support Doug with his new server project ) To top it all off, in the Febr08 number of Ciel et Espace there is an article describing a new competitor for MOND, called MOG for Modified Gravity theory. The Pioneer anomaly, which started as a fairly low-key issue, seems on the up again now that Newtons law is shaking, at least in the low acceleration regime. What will be next?? Instead of citing the names of the authors, apologies if I should have done so, here is the link to Messenger #128. Read for yourself! http://www.eso.org/sci/publications/messen...enger-no128.pdf |
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Jan 30 2008, 02:04 AM
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#229
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Member Group: Members Posts: 723 Joined: 13-June 04 Member No.: 82 |
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Mar 31 2011, 05:28 AM
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#230
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Senior Member Group: Members Posts: 1598 Joined: 14-October 05 From: Vermont Member No.: 530 |
New work on thermal modeling the affect of IR scattering off of the back of the HGA purports to explain the entirety of the anomaly:
http://www.technologyreview.com/blog/arxiv/26589/ |
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Jul 22 2011, 05:39 AM
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#231
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Senior Member Group: Members Posts: 1598 Joined: 14-October 05 From: Vermont Member No.: 530 |
And NASA takes another look:
http://www.technologyreview.com/blog/arxiv/27012/ (Links to referenced papers in both this and the last article.) |
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Jul 22 2011, 04:23 PM
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#232
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Member Group: Members Posts: 723 Joined: 13-June 04 Member No.: 82 |
From Support for temporally varying behavior of the Pioneer anomaly from the extended Pioneer 10 and 11 Doppler data sets
"The main question is whether or not a statistically significant anomalous acceleration signal still remains in the residuals after the thermal recoil force has been properly accounted for. Results of this meticulous study will be published soon." Unfortunately, the paper does not appear to give error bars. Assuming that the error bars are small enough that the above diagram (especially the "Stochastic Acceleration" portion) is reasonably accurate, it looks to me like the acceleration curve flattens out to an asymptotic value of about 7 x 10^-10 ms^-2. The most obvious cause, in my opinion, would be an exponential decaying acceleration with a half-life of about 3-4 years (declining due to radioactive decay in the RTG?) plus a steady acceleration of unknown origin of about 7 x 10^-10 ms^-2. Of course I am no expert. |
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Jul 23 2011, 12:15 AM
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#233
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Oct 5 2011, 03:27 PM
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#234
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Member Group: Members Posts: 153 Joined: 14-August 06 Member No.: 1041 |
The name of the game has always been to grow the thermal differentiation to the point that the error bars overlap the known radioactive decay profile; providing a plausible solution.
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May 12 2012, 09:27 AM
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#235
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Member Group: Members Posts: 212 Joined: 19-July 05 Member No.: 442 |
The name of the game has always been to grow the thermal differentiation to the point that the error bars overlap the known radioactive decay profile; providing a plausible solution. Looks like the mystery has been solved... Pioneer Anomaly Solved: The Planetary Society I'd also heard that the ESA was considering a mission to probe the effect, but I've not been able to find out much about it. |
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May 12 2012, 11:25 AM
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#236
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
I'd also heard that the ESA was considering a mission to probe the effect, but I've not been able to find out much about it. see for example A Mission to Explore the Pioneer Anomaly, OSS (Outer Solar System): A fundamental and planetary physics mission to Neptune, Triton and the Kuiper Belt, Odyssey 2 : A mission toward Neptune and Triton to test General Relativity |
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May 12 2012, 12:11 PM
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#237
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Member Group: Members Posts: 903 Joined: 30-January 05 Member No.: 162 |
LOL, sounds like UMSFs crack Ice Hunters might get a new gig.
Let's go get 'em a big un !! |
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May 18 2012, 10:03 AM
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#238
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Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
Not much reason to send one entire new mission or studies IMO.
The case might be quite closed and filed after JPL have had another look at the matter. The paper by Francisco, Bertolami and Páramos is found here: http://arxiv.org/pdf/1103.5222v2 |
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