Pioneer Anomaly

I think what is partly responsible for global warming is also affecting the path of these spacecrafts. The orbital dynamics of all bodies within the solar system should be affected.

Therefore, if the pioneer spacecrafts are not within reach of the gravitational field of another star, these will slow down, and their trajectory will bring them barreling back towards our own sun.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Jim</i>
<br />A heat radiator will not cause anything to accelerate because it is just blackbody radiation and nothing of any mass is being radiated. You can't have any action from f=ma when m=0.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">I would fully agree with this. As shown on my webpage www.physicsmyths.org.uk/photons.htm , the concepts of mass and momentum can not be applied to light, and as indicated under www.physicsmyths.org.uk/#radpress even the classical theory of 'radiation pressure' is flawed. Escape of spacecraft heat is therefore certainly not the cause of the 'anomalous acceleration' (it would anyway by an unlikely coincidence that the same amount of heat would escape from all probes).

---

www.physicsmyths.org.uk
www.plasmaphysics.org.uk

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
Why do your arguments consistently ignore Ulysses, which shows the same anomaly but orbits the Sun and never gets much farther out than Jupiter;<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">I think that the Ulysses data are very questionable in this context. The point is that radiation pressure is thought to be 10 times more effective in magnitude than the 'anomalous acceleration' effect near Jupiter (and even more closer to the sun)(see the very recent re-analysis by Anderson et al. arxiv.org/PS_cache/gr-qc/pdf/0104/0104064.pdf , page 28). Any error in the radiation pressure modelling will therefore cause residuals that could produce the observed difference (Anderson et al. point even out in their paper that there is a strong correlation of the 'anomalous acceleration' data to the radiation pressure in the Ulysses data (page 22 of their paper). Even probes in the vicinity of Saturn would still be severely affected by the sun, so I think it is no coincidence that the 'anomalous acceleration' data are limited to the Pioneer probes and start only at around 20 AU.

---

www.physicsmyths.org.uk
www.plasmaphysics.org.uk

Has anyone done the math to see how far off course the probe should be and check to see if in fact the probe is off that much? I'm not very good at it but over 10 years or so even at a small acceleration the probe would be a long way from where it should be.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Jim</i>
<br />Has anyone done the math to see how far off course the probe should be and check to see if in fact the probe is off that much? I'm not very good at it but over 10 years or so even at a small acceleration the probe would be a long way from where it should be.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">As I mentioned above already, the range and Doppler data of the Pioneer probes suggest that they are 400 000 km (roughly the earth-moon distance) behind where they should be (the value for the 'anomalous acceleration' is derived from this) and this is also what you would expect due to the fact that the travel time of the telemetry signal is being evaluated incorrectly (the distance to the spacecraft is underestimated by the distance the spacecraft travels whilst the signal travels from and to earth).

---

www.physicsmyths.org.uk
www.plasmaphysics.org.uk