A What could potentially explain the onset of the Pioneer Anomaly?

[GravityBound]

With regard to solar radiation effects causing the onset of effect, have any here investigated whether this is consistent with the observed residuals? Because the power of solar radiation is proportional to inverse square of distance from the Sun, it seems plausible to me that the mis-modeled effect of which Turyshev,etal speak is an under-modeling of solar radiation effects that fit a function of inverse square of distance from Sun. Even so I find that the residuals of Anderson, etal do not differ from the thermal model of Turyshev,etal by a function well correlated to inverse square of distance. If sufficient mismodeling (prop to 1/AU^2) is employed the fit isn't good but the onset is indicated.

It's not the thermal model I am questioning but the explanation of the cause of onset. That "Figure 2" is suggestive of the possibility that solar radiation effect may be the cause or at least part of the cause of the onset of effect is a reasonable intuition as far as I am concerned. Even so, getting the numbers to work is problematic when mismodeled solar radiation effects are modeled to be proportional to 1/AU^2.

 

[rootone]

You need to post a link to the paper/other publication, or whatever you are referring to.

 

[GravityBound]

You need to post a link to the paper/other publication, or whatever you are referring to.

Sure. I just figured that any who might respond would be familiar with the published research.
The original study (Anderson, etal) from which one may obtain the residuals of Pioneer 11's onset https://arxiv.org/abs/gr-qc/0104064v5
The study on anisotropic thermal effects (Turyshev, etal) from which one may obtain the proposed thermal effects. https://arxiv.org/abs/1204.2507v1.

Just to be clear. I am not wanting to expand a discussion of what, if anything, is amiss with the hypothesis here. I am seeking others who may have examined the hypothesis and wish to know if they are fully satisfied with the hypothesis as an "explanation" or "model" of onset.

 

[berkeman]

@GravityBound -- Welcome to the PF.

Have you done a PF search on this subject yet? There have been several long threads over the years here. You can also find several of them listed in the "Similar Threads" links at the bottom of the page.

 

[rootone]

Thanks for the link.
I also heard that the Juno spacecraft was slightly adrift of where it should have been on it's second bypass of Earth.
The only idea that made sense to me is that is that it might have been slowed a bit by passing through a comet trail of gas or such,

 

[GravityBound]

@GravityBound -- Welcome to the PF.

Have you done a PF search on this subject yet? There have been several long threads over the years here. You can also find several of them listed in the "Similar Threads" links at the bottom of the page.

Yes, I did. But there is little regarding the onset of effect mentioned in those threads. From my perspective I do think that the thermal model is the primary effect at larger distances from the Sun (ie Pioneer 10 residuals), Pioneer 11 data covers what Pioneer 10 did not and the difference between a thermal model and the observation of Anderson etal are poor fit to any reasonable solar model IMHO. So I think it is reasonable to question whether there are other effects at play. If one reads Turyshev, etal. they, in so many words, say that leading into and closely following the Saturn encounter, the residuals varied through a broad range of magnitudes and so questioned whether there is an "onset". The fluctuation exceeded the thermal effects more than 2 fold. Whatever the case, it is certainly true that these observations (which did not participate in their report) are not consistent with the solar radiation hypothesis of onset observations.

I'll glance back from time to time to see if this thread attracts any comments of interest to me.

Oh ... and thank you for the welcome!