Pioneer Deceleration - More NASA BS About to be spilled!

I think more gravitational pull from more than one BIG object!

I think a lot of people at NASA are going to end up bald from this -

This blog post at Cosmic Variance:
[link to blogs.discovermagazine.com]
and the Popular Science article:
[link to www.popsci.com]
provide more details about the pioneer anomaly and the new attempt to explain it with known physics. Unfortunately (at least as far as I know) the paper hasn't been published anywhere yet, so we don't know how much of the anomalous acceleration they can actually debunk.

LOL yup yup, from dreaming up all those stories to concoct!

But the more they spin, the more it gets transparent.

Ahhh you are a wise one - I guess you feel as I do that they are already looking at these papers and getting ready to shill it all to death???

They're both the exact same design, so if a design flaw caused asymetrical heating it would cause an acceleration with the same velocity vector on both craft and indeed both craft are experiencing the same acceleration in the same sun-ward direction.

It's not due to any Planet X or Nibiru however; Pioneer 10 and 11 are heading out of the solar system in opposite directions, yet both experienced the same unexpected "tug" towards the sun, ruling out an unseen body at the edges of the solar system being the cause. If it were due to such a body then one probe should have felt an acceleration away from the sun while the other probe would have felt a weaker acceleration towards the sun (due to it being on the opposite side of the solar system and also much further away from the perturbing body). Instead they both experienced the same acceleration in a sunward direction, so either it's due to identical design flaws on the probe, a distance-dependent change in gravity similar to MOND, or some other unknown factor slightly affecting doppler measurements at great distances.

Last Edited by Astromut on 03/11/2011 10:00 AM

It clears it up s bit - but both craft are at marked different distances - even with a design flaw, which can't be the case it would be down to probable aging of the craft and wear - any slow down theoretically could be down to an outside influence other than the sun. Wouldn't the exact same slowdown of the craft at different distances of millions of miles be an astronomical ratio of chance?

Why couldn't a design flaw account for that? If they're leaking the same amount of heat asymetrically because of how they were designed... then wouldn't they experience the same acceleration? Doppler measurements of the spacecraft were expected to be able to measure each craft's acceleration down to 10^-10 meters/second^2 ( [link to www.oca.eu] ) so this is near the limit of detection which is why there's about 15% of standard error in the figure. The raw numbers for the spacecraft are not literally exactly the same, but are within a 10^-10 m/sec of each other so any difference, if any exists, is essentially too small to actually be accurately measured.
[link to www.oca.eu]
From 1998 the figures were (see in the above paper):
(8.09 ±0.20) ×10^-8cm/s2 for Pioneer 10
(8.56 ±0.15) ×10^-8cm/s2 for Pioneer 11

Last Edited by Astromut on 03/11/2011 11:00 AM

I'm not questioning your obvious knowledge of the matter but (8.09 ±0.20) ×10^-8cm/s2 for Pioneer 10 (8.56 ±0.15) ×10^-8cm/s2 for Pioneer 11, is quite a difference is it not - and anyhow those figures are quite old.

But for instance a design fault would have been picked up by now. If you drove your car around for 30 years without the realization it had a design flaw it would have to be one within an internal component.

Being that they are over 30 years old that makes wear and tear more feasible.

But the speed of slowdown even with those maths is in no way similar.

The same paper states the accuracy of the measurements to be within about 10^-8cm/s2. A difference less than about 1x10^-8cm/s2 is essentially noise. Since both probes are dead those are about as new as you're going to get on the measurements too; nothing's transmitting now.

But for instance a design fault would have been picked up by now. If you drove your car around for 30 years without the realization it had a design flaw it would have to be one within an internal component.


This isn't a car. The design flaw, if its the cause, doesn't cause any other noticeable problem. The probe doesn't care that it's asymetrically leaking heat and the effect was far too small to effect their manuevers during the main mission.

But the speed of slowdown even with those maths is in no way similar.

Actually, that's just my point; it is similar, it's less than 1x10^-8cm/s2 apart.

sorry guys but the explaination is a very simple one, so simple it is beyond the grasp of of the Physics groupies.
The Spacecraft are not traveling at a velocity great enough to escape the Solar system, they will become just more junk orbiting the Sun.

Yes, they are. Far above solar escape velocity, in fact.

Perhaps space is nothing but a snowglobe and both craft are nearing the glass.