PDA

View Full Version : Pioneer anomaly flyby anomaly



bane357
2014-Jul-17, 09:51 AM
I have a few questions.
Is there a link between Pioneer anomaly and flyby anomaly?

OK They solved Pioneer anomaly. They used thermal model of the two spacecraft Pioneer 10 and Pioneer 11.

http://arxiv.org/abs/1204.2507

Astrophysicist Slava G. Turyshev said

” We still have an uncertainty in our study of less than 18 percent. But for me, this is the answer. Some may argue it is not final, but in my mind we did a good job, and it's very clear what happened.”

http://www.slate.com/articles/health_and_science/new_scientist/2012/08/the_pioneer_anomaly_heat_generators_slowed_down_pi oneer_10_and_11_in_deep_space_.html

In article we can read

http://arxiv.org/pdf/gr-qc/9808081v2.pdf
” Radio metric data from the Pioneer 10/11, Galileo, and Ulysses spacecraft indicate an
apparent anomalous, constant, acceleration acting on the spacecraft with a magnitude ∼
8.5 ื 10 −8 cm/s 2 , directed towards the Sun.”

ap∼ 8.5 ื 10 −8 cm/s 2

Did they used their thermal model to explain anomaly for Galileo, and Ulysses spacecraft, or only used thermal model for Pioneer 10 and Pioneer 11?

Here is one intresting article

http://archive.today/YvUP#selection-507.173-507.192

”Gary Page of George Mason University in Fairfax, Virginia, and his colleagues have identified 15 asteroids that might also be subjected to the mysterious force. The asteroids' orbits all stretch far into the outer ...”

http://arxiv.org/abs/astro-ph/0504367

Doppler residuals (observed minus computed data) is very important. Doppler residuals (frequency residuals) is linked to ap, so if anyone wants to explain anomaly, he should explain origin of Doppler residuals or ap. In case Pioneer anomaly they used thermal model.

In case fly by anomaly Doppler residuals should be explaind too.
” While the Doppler residuals (observed minus computed data) were expected to remain flat, the analysis revealed an unexpected 66*mHz shift, which corresponds to a velocity increase of 3.92 mm/s at perigee. “

http://en.wikipedia.org/wiki/Flyby_anomaly

tusenfem
2014-Jul-17, 01:04 PM
As this seems to be more of a discussion about the anomalies, I have moved this to S&T.
However, bane357, do not post your ATM ideas in this thread!

Reality Check
2014-Jul-18, 01:47 AM
Is there a link between Pioneer anomaly and flyby anomaly?
The quick answer is no, bane357. since none of your citations state this :D.

An quick calculation hints at no: The Pioneer anomaly is an acceleration towards the Sun of (8.74ฑ1.33)ื10−10 m/s2. (8.74ฑ1.33)ื10−7 mm/s2 This is So it would take 107 seconds to change velocities by ~9 mm/s or 115 days. Flybys are hours or a few days under the dominant influence of the Earth.

The 33 results from ADS (http://www.adsabs.harvard.edu/) for "flyby anomaly pioneer" include (the rest look irrelevant to your question):
High precision thermal modeling of complex systems with application to the flyby and Pioneer anomaly (http://adsabs.harvard.edu/abs/2011AnP...523..439R)

The analysis outlines that thermal recoil pressure is not the cause of the Rosetta flyby anomaly but likely resolves the anomalous acceleration observed for Pioneer 10.