The effect was first noted by Dr. John D Anderson...
www.planetary.org/about/press/news/2008/0516_Newton_Einstein_Lost_in_Space.html "As it sped through space, a specialist in radio-wave physics named John Anderson at NASA's Jet Propulsion Laboratory noticed an odd thing. The spacecraft was drifting off course. The discrepancy was less than a few hundred-millionths of an inch per second for every second of spaceflight, accumulating year after year across billions of miles. Then Pioneer 11, an identical probe escaping the solar system in the
opposite direction, also started to veer off course at the same rate.
Ordinarily, such small deviations might be overlooked, but not by Dr. Anderson. He monitored the trajectories six years before calling attention to the matter. "I'm a little like an accountant," Dr. Anderson said. "We have Newton's theory and Einstein's theory, and when you apply them to something like this -- and it doesn't add up -- it bothers me.""
Bio...
stardust.jpl.nasa.gov/news/bio_anderson.htmlDr. John D Anderson
Main 'torch carrier'
www.space.com/scienceastronomy/mystery_monday_041018.html"Devoted to the problem"
Slava Turyshev at NASA's Jet Propulsion Laboratory is one of a handful of scientists who wrestle mentally with the Pioneer anomaly every day. He is not paid to work specifically on the problem, so he has to juggle the disturbing thought with his regular research, which involves other aspects of gravity and, significantly, whether theories that explain the glue of the whole universe might one day match neatly with those describing the invisible, subatomic world.
"I have been working on [the Pioneer anomaly] for more than 11 years now, and was never funded to do this job," Turyshev tells SPACE.com. "I guess this says a lot about my devotion to solve this mystery.""
Bio...
science.jpl.nasa.gov/people/Turyshev/Are they having a 'slow news' day? The DT article is 'sigged' and dated...
"By Robert Matthews, Science Correspondent
Published: 12:01AM GMT 10 Feb 2002" and reference to it is made at this site...
www.sott.net/articles/show/215168-Mysterious-force-holds-back-Nasa-probe-in-deep-space it requotes 'Dr Laing, of the Aerospace Corporation of California.*' as saying ' "If the effect is real, it will have a big impact on cosmology and spacecraft navigation," '
The relevance of the remarks comes from [it is understood] His involvement in data processing project and not from the Aerospace Corporation.
The Planetary Society members have donated to allow interpretation of the Pioneer 10/11 data. The FAQ's for this project can be seen here...
www.planetary.org/programs/projects/innovative_technologies/pioneer_anomaly/update_20050720.htmlIdeas/theories have varied over time, here...
arxiv.org/PS_cache/gr-qc/pdf/0405/0405076v1.pdf 'The nonsymmetric gravitational theory leads to a modified acceleration law that can at intermediate distance ranges account for the anomalous acceleration experienced by the Pioneer 10 and 11 spacecraft.'
Through....
tech.dir.groups.yahoo.com/group/piclub/message/665"The main thing I noticed is that its magnitude is almost
exactly 2*Pi*G (a nice round number, so to speak)."
At the other end of the scale...
"Junior Member
quantum lies
The best way I can explain the slow downs, and speed up of the spacecrafts, is that a kind of quantum remembering has occurred.
Double split experiments with lasers show that the gates where there is threat of knowing which side the photo or electron goes through will change the outcome.
As if once the experiment is started, the results will start to learn, and change before the sensor is even turned on.
This idea of quantum remembering also has a flip side of quantum foretelling.
It is as if the universe has a memory of what happened on the pioneer flights, and is making up for lost time with speedups of later spacecraft.
I wonder if the universe is an optical illusion, and does not become real unless a spacecraft goes to that star or planet, and changes the outcome from a wave image to something real."
"Established Member
'It is as if the universe has a memory'
But...What if the universe, due to its old age, has developed altzeimer's??"
But the idea holding sway at the moment...
www.newscientist.com/article/dn13676 "Turyshev suspects that the optical properties of the spacecraft's exterior may have changed during the mission, possibly degrading due to dust hitting the craft and ultraviolet radiation from the sun.
That might make the spacecraft radiate more heat than expected. However, it's not clear yet whether these changes to the spacecraft's exterior could account entirely for its unexpected trajectory."
and bourne out by this...
www.newtonphysics.on.ca/anomalous/index.html"This paper shows that the anomalous acceleration of the spacecraft Pioneer 10 and 11 in the direction of the Sun is due to the presence of dust in the Kuiper belt, which has been ignored in the calculation. These data provide the first direct measurement of dust density in the Kuiper belt, which is 1.38 x 10-19 gr/cc."
by Paul Marmet, Ph. D. (1932-2005)
Last real 'official' Team Meeting...
"The Pioneer Explorer Collaboration: Investigation of the Pioneer Anomaly at ISSI"
www.issibern.ch/teams/Pioneer/of the many documents published on this subject, the three main useful ones were...
trs-new.jpl.nasa.gov/dspace/bitstream/2014/38552/1/05-3863.pdf 'A Route to Understanding of the Pioneer Anomaly
aSlava G. Turyshev, bMichael Martin Nieto, and cJohn D. Anderson'
arxiv.org/PS_cache/gr-qc/pdf/0603/0603016v2.pdf'The Pioneer anomaly: seeking an explanation in newly recovered data
Viktor T Toth and Slava G Turyshev'
arxiv.org/PS_cache/gr-qc/pdf/0512/0512121v2.pdf'The Study of the Pioneer Anomaly:
New Data and Objectives for New Investigation
Slava G. Turyshev,a Viktor T. Toth,b Larry R. Kellogg,c Eunice. L. Lau,a and Kyong J. Leea'
Line drawing 'Pioneer'
history.nasa.gov/SP-349/p48.htm I don't think it was a 'slow news' day but that, perhaps, the final report is due to be published shortly.
Conclusion...
Despite determined efforts by Slava G. Turyshev et. al. a definitive reason for the Pioneer Anomaly has yet to be uncovered. It vindicates NASA's perceived [by me] lack of official involvement on the basis that any progress would not be made. It speaks well for those same people to take their own time to solving the problem.
Future project that may help to solve the 'Pioneer Anomaly'
IKAROS Project
www.jspec.jaxa.jp/e/activity/ikaros.html'IKAROS' Wiki
en.wikipedia.org/wiki/IKAROSIt deals with the 'photon acceleration' from the Sun and seems to be a candidate to help explain further the anomaly. What do You think?
StuartG