Actually, while it's equipotential with respect to altitude, it's not equipotential with respect to total energy. Don't forget objects at the equator, include the surface of the ocean, is travelling about 1,000 mph faster, Eastward, than the poles. This is rocket launches take place in more Southern regions.

As for the rest of the article on Pioneer 10, couldn't tell you.

Are there radios of two frequencies, though? Different freqs are slowed down by interferring medium (gas/dust) at different rates. This is one means GPS uses to detect/adjust for ionosphere abberations. If P-10 had two radios, sending a ping on both and measuring the different times we received it might tell us not only redshift, but actual distance, as well as the density of the medium through which it's travelled.

But I'm sure the rocket scientists have thought of this!

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I am Mugs, of the Alien clan of Usa, Nordamerica, a Terran, of Sol.

Mine: "Perception isn't reality. It's merely an abstraction thereof, and quite often not a very good one at that."

Heinlein's: "Staying young requires the unceasing cultivation of the ability to unlearn old falsehoods." "Freedom begins when you tell Ms. Grundy to go fly a kite."

In my opinion, the Pioneer anomaly is a demonstration of the Scharnhorst effect. Klaus Scharnhorst predicted that light propagating through a rarified quantum vacuum field (i.e. a vacuum in which a range of frequencies of virtual pairs is suppressed, as in a Casimir gap) should move faster than light that is propagating through an equivalent vacuum. Light can travel faster through propagating media that are less dense, and the shortened return times lead us to believe the probes are closer than they really are, and if we believe that the speed of light in a vacuum must be constant, we interpret this to mean that the probes are slowing. They are not.

I would like to explain further, but the explanation would be regarded as ATM. The summary of the vacuum polarization model is located here.

What if a nonscientist....my model of quantum gravity

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The ether of general relativity therefore differs from that of classical mechanics or the special theory of relativity respectively, in so far as it is not 'absolute', but is determined in its locally variable properties by ponderable matter.

Albert Einstein, "On the Ether", 1924

30 Years of Pioneer Spacecraft Data Rescued:
The Planetary Society Enables Study of the Mysterious Pioneer Anomaly

I used to work with tapes just like the one depicted....

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Everything I need to know I learned through Googling.

Moved to Astronomy section.

Used to be able to carry 22 on each arm in my days as a tape librarian.

Fortunately I never needed to carry 22 at a time. I remember having to make four tapes (four copies) to deliver some of my software, though.

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Everything I need to know I learned through Googling.

According to Michael Nieto of the Los Alamos National Laboratory in New Mexico, the data for Pioneer 10 was not precise enough around the time of its fly-by of Jupiter to indicate whether its acceleration problems began with that encounter. But, this may soon be remedied. JPL's Slava Turyshev recently unearthed archived data from Pioneer 10 and 11 and is reconstructing the missions in their entirety, which could help determine whether Pioneer 10's anomaly began with a fly-by too.

"That's what I want to look at more precisely" - Michael Nieto .

The researchers say that while it is possible that an overlooked effect from ordinary physics might account for the anomalies, something more exotic could also be involved. For example, the spacecraft trajectories could be influenced by the presence of dark matter in the solar system. Or maybe the laws of gravity need reworking.
Peter Antreasian, a spacecraft navigation expert at JPL who along with Joseph Guinn first brought attention to the anomalies seen in Galileo and NEAR during their Earth fly-bys, believes that it will require a modified law of gravity or other new physics to explain it. He does not think it is connected to the Pioneer anomaly, since the force behind this seems always to point in the same direction, back towards the sun. In the Earth fly-bys, by contrast, "a directional force such as the Pioneer anomalous force would have been very evident in the radiometric data in the last few days before the approach". Whatever causes this anomaly seems to make its impact just a few minutes before the closest approach to Earth.
Not everyone is convinced the Earth fly-by anomaly points to new physics. Myles Standish, who calculates trajectories of solar system bodies for JPL, says he feels the Earth fly-by anomaly is almost certainly due to an error in measurement or an incomplete analysis using ordinary physics.

http://www.newscientist.com

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`Irony` actually does mean `metal like`...

I'm intrigued by this statement, because it's something I've wondered about. Has the Pioneer anomaly been convincingly shown to be toward the sun? Because I understood there were three possibilities: (1) that it was toward the earth, indicating some measurement anomaly; (2) that it was toward the sun, indicating a gravitational anomaly; or (3) that it was in the trajectories, indicating something like dark matter slowing them down.

I think that if it is accepted that the acceleration is toward the sun, then gravity is the place to look for an explanation.

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As above, so below

Hum,
this is what the `new` data hopes to solve.

Flybys may be key to Pioneer anomaly (Subscription)

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`Irony` actually does mean `metal like`...

I wonder what the temperature of the outer surfaces of the spacecraft are at this great distance from the sun. Perhaps they are so cold that ambient water and other molecules are condensing on them to make them get heavier from ices? Like comets forming. This in itself shouln't change the acceleration (all weights fall at the same rate), but maybe the condensation causes a drag?

I've been away from this thread for quite a while. I think you should write a paper on this and include the IRAS figure with it. Cool info!!! Print it upside down since this wouldn't affect the conclusions.

Computer sleuths try to crack Pioneer anomaly

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Everything I need to know I learned through Googling.

Neito & Co are not convinced the 'force' is strickly toward the sun. One of the reasons they wanted the earlier Pioneer data preserved, was to determine if there is an unexpected vector. Thanks to the Planetary Society, this data is being analysed, and we should get a better answer.

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jwj

If you always believe what you already know, you can't learn anything - Liz

One wonders if it had a close encounter with a small Kuiper Belt object. Not a hit, but close enough to affect it gravitationally and thus alter its acceleration and trajectory.

Is he the spokesman for Professor Alden?

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One thing I am curious about. Everyone talks about it as the Pioneer Anomaly, but what about the Voyagers? Has anyone every detected any similar anomaly with them?

I've been told that due to their nature the Voyagers cannot be used for this purpose. Something to do with the way the Voyagers keep themselves aligned.

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"I'm as accurate as any psychic. And I'm a cartoon!" -- Squidward

"Arrrgh, the laws of physics be a harsh mistress!" -- Bender

Voyagers use reaction mass to stabilize, the Pioneers were spin stabilized.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.

Newfound Data Could Solve NASA's Great Gravity Mystery

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Everything I need to know I learned through Googling.

Pioneer Anomaly Project Update

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Everything I need to know I learned through Googling.