IPB

Welcome Guest ( Log In | Register )

The Pioneer Anomaly
remcook
post Aug 16 2005, 04:27 PM
Post #1


Rover Driver
****

Group: Members
Posts: 1015
Joined: 4-March 04
Member No.: 47



http://www.planetary.org/news/2005/pioneer_anomaly_faq.html

The planetary society may be checking it out...

QUOTE
The Planetary Society has committed to raise the funds to preserve the priceless Pioneer data from destruction.


After years of analysis, but without a final conclusion, NASA, astonishingly, gave up trying to solve the "Pioneer Anomaly" and provided no funds to analyze the data. The Pioneer data exists on a few hundred ancient 7- and 9-track magnetic tapes, which can only be read on "antique" outdated computers. The agency is going to scrap, literally demolish, the only computers able to access and process that data in the next few months!
Go to the top of the page
 
+Quote Post
 
Start new topic
Replies
Guest_Richard Trigaux_*
post Aug 18 2005, 06:59 AM
Post #2





Guests






As far as I understand from readings in the press, the Pioneer probes (ant others) would slow down slighty more than expected from only the Sun gravity. This led to some interesting but far reached speculations.

Some asked if the gravity law was not exactly 1/R2.

The most consistent speculation is that, like the galaxy shows an excess (sometimes ten times) of invisible mass, called dark matter, the solar system may have some too (although much less, a fraction of a %). From close to the Sun, we feel only the Sun's attraction, but further in space we feel the Sun's more the dark matter's attraction. This could be explained if the dark matter is made of low energy subatomic particles; many would orbit the galaxy, with speeds in the 200km/s range. Some would orbit the Sun with still smaller speeds in the km/s range.


But the measurement of the anomaly is based on many far-reached and difficult estimates, such as the toss of sun's light on the space probe, or gaz leak from the reservoirs. A slight error or false assumption, and the result would be very different. This is why the Pioneer anomaly did not upset the science community. A precise measurement of this anomaly would perhaps do.
Go to the top of the page
 
+Quote Post
The Messenger
post Aug 26 2005, 09:08 PM
Post #3


Member
***

Group: Members
Posts: 624
Joined: 10-August 05
Member No.: 460



QUOTE (Richard Trigaux @ Aug 17 2005, 11:59 PM)
As far as I understand from readings in the press, the Pioneer probes (ant others) would slow down slighty more than expected from only the Sun gravity. This led to some interesting but far reached speculations.

...
But the measurement of the anomaly is based on many far-reached and difficult estimates, such as the toss of sun's light on the space probe, or gaz leak from the reservoirs. A slight error or false assumption, and the result would be very different. This is why the Pioneer anomaly did not upset the science community.  A precise measurement of this anomaly would perhaps do.
*


Painstaking and careful analysis is a more exacting description.

http://arxiv.org/find/astro-ph/1/au:+Turys...S/0/1/0/all/0/1

http://arxiv.org/abs/gr-qc/0104064

http://arxiv.org/abs/gr-qc/9906112

Anderson, Nieto & Turyshev's paper- rebuttal - papers with the astrophysical community spans more than a decade now, and signatures of the anomalies have been found everywhere they have found the time and money to look for them.

The community should be giving this type of research highest priority -

Nowhere is it written in stone gravity behaves exactly as was predicted and observed a more than a century ago. If the observational data indicates otherwise, why are we so certain the status que is the status correct?
Go to the top of the page
 
+Quote Post
antoniseb
post Aug 26 2005, 10:42 PM
Post #4


Member
***

Group: Members
Posts: 235
Joined: 2-August 05
Member No.: 451



QUOTE (The Messenger @ Aug 26 2005, 04:08 PM)
The community should be giving this type of research highest priority


The highest priority? I think finding all substantial Earth Crossing asteroids would be more important. Basic exploration of the Solar System should be more important. Looking for extra-solar planets should be more important. Galactic census missions should be more important. Studies of Sgr A* and the things orbiting it should be more important. Studies of distant Type 1a Supernova should be more important. etc.

The ESA has considered launching a probe specifically to measure this effect with greater precision, but it didn't get funded.

Perhaps you could tell us how you would probe this phenomenon, and what the various outcomes would tell us? Then we can talk about priorities.
Go to the top of the page
 
+Quote Post
The Messenger
post Aug 29 2005, 05:25 PM
Post #5


Member
***

Group: Members
Posts: 624
Joined: 10-August 05
Member No.: 460



QUOTE (antoniseb @ Aug 26 2005, 03:42 PM)
The highest priority? I think finding all substantial Earth Crossing asteroids would be more important. Basic exploration of the Solar System should be more important. Looking for extra-solar planets should be more important. Galactic census missions should be more important. Studies of Sgr A* and the things orbiting it should be more important. Studies of distant Type 1a Supernova should be more important. etc.

The ESA has considered launching a probe specifically to measure this effect with greater precision, but it didn't get funded.

Perhaps you could tell us how you would probe this phenomenon, and what the various outcomes would tell us? Then we can talk about priorities.
*


Two things:

1) I would take the mother-and-hen approach suggested by Nieto. Pioneer 10 & 11 demonstrated the virtues of simple, spin stabilized, thermally balanced probes. I would add a lot of health monitoring gear, but otherwise the probes should be very simple. They should have transmitters capable of using both phase-locked loop and ultra-stable oscillator ranging frequency control, multiple bands.

There should be at least two different types of chicks - one designed with a great deal of solar drag, the second fairly streamlined. Placed into identical trajectories at the same time, this would allow differentiation of unknown forces from solar wind effects. Perhaps even better would be ‘umbrella chicks’ that could trade-off between solar sail and coast modes, thus keeping the clutch together.

The mother should hover close enough to calibrate and study emissivity and radiation, but distant enough not to disturb momentum.

2) If one assumes the Pioneer anomalies are real and not artifacts, there should be supportive evidence, and many fundamental implications.

The solar wind may not be the only force moving objects away from the center of the solar system. Anderson had to add a linear component to the solar wind to model the acceleration of Galileo and Ulysses: http://arxiv.org/PS_cache/gr-qc/pdf/0104/0104064.pdf p21:

QUOTE
The radio Doppler and ranging data can be fit to the noise level with a time-varying solar constant
in the fitting model [82]. We obtained values for the time-varying solar constant determined by Ulysses
FIG. 10: Galileo best fit Doppler and range residuals using CHASMP. navigational data during this south polar pass [81]. The inferred solar constant is about 40 percent larger at perihelion (1.3 AU) than at Jupiter (5.2 AU), a physical impossibility!

We sought an alternative explanation. Using physical parameters of the Ulysses spacecraft, we first converted the time-varying values of the solar constant to a positive (i.e., outward) radial spacecraft acceleration, ar, as a function of heliocentric radius.


(my bold)

Throw a spring constant into elliptical orbits, as Anderson did to model Ulysses, and all hell breaks loose. Fly-bys and orbits don’t return correct planetary masses, long distance navigation breaks down, and gravity anomalies crop up everywhere.

Such a force is consistent with known observational facts. Figuring out if it is real should be given highest priority.
Go to the top of the page
 
+Quote Post

Posts in this topic
- remcook   The Pioneer Anomaly   Aug 16 2005, 04:27 PM
- - remcook   Some background reading... http://arxiv.org/find/...   Aug 16 2005, 04:40 PM
|- - tedstryk   Won't New Horizons be spin stabilized when not...   Aug 16 2005, 06:53 PM
|- - Jeff7   QUOTE (remcook @ Aug 16 2005, 11:40 AM)Some b...   Aug 17 2005, 07:09 PM
- - remcook   Quote from alan stern: QUOTE Yes, we spin most of...   Aug 16 2005, 07:43 PM
- - Richard Trigaux   Could not the Pioneer tapes be saved on a more mod...   Aug 17 2005, 06:37 AM
- - remcook   QUOTE It looks like the Pioneers have long stopped...   Aug 17 2005, 08:09 PM
- - deglr6328   QUOTE (remcook @ Aug 17 2005, 08:09 PM)that...   Aug 17 2005, 11:10 PM
|- - Bob Shaw   QUOTE (deglr6328 @ Aug 18 2005, 12:10 AM)Not ...   Aug 18 2005, 08:24 AM
- - Richard Trigaux   As far as I understand from readings in the press,...   Aug 18 2005, 06:59 AM
|- - The Messenger   QUOTE (Richard Trigaux @ Aug 17 2005, 11:59 P...   Aug 26 2005, 09:08 PM
|- - antoniseb   QUOTE (The Messenger @ Aug 26 2005, 04:08 PM)...   Aug 26 2005, 10:42 PM
|- - The Messenger   QUOTE (antoniseb @ Aug 26 2005, 03:42 PM)The ...   Aug 29 2005, 05:25 PM
|- - algorimancer   It seems to me that a simple means of checking thi...   Aug 29 2005, 05:40 PM
|- - The Messenger   QUOTE (algorimancer @ Aug 29 2005, 10:40 AM)I...   Aug 29 2005, 06:12 PM
- - edstrick   Climate orbiter was not radar tracked, it was tran...   Aug 30 2005, 08:52 AM
|- - Mongo   QUOTE (edstrick @ Aug 30 2005, 08:52 AM)There...   Aug 30 2005, 07:12 PM
|- - Bob Shaw   Bill: Your links, er, don't! Bob Shaw   Aug 31 2005, 11:28 AM
|- - Mongo   That's strange; I just clicked on them and the...   Aug 31 2005, 02:45 PM
|- - Bob Shaw   QUOTE (Mongo @ Aug 31 2005, 03:45 PM)That...   Aug 31 2005, 03:42 PM
|- - Mongo   QUOTE (Bob Shaw @ Aug 31 2005, 03:42 PM)I pro...   Aug 31 2005, 03:57 PM
- - The Messenger   I am at least as interested in the flight path ecc...   Aug 31 2005, 06:56 PM
|- - antoniseb   QUOTE (The Messenger @ Aug 31 2005, 01:56 PM)...   Aug 31 2005, 09:58 PM
- - dvandorn   Hmmm... well, the effect must be very, very minor ...   Aug 31 2005, 07:24 PM
- - Richard Trigaux   Thanks to recent posters this thread took an inter...   Sep 3 2005, 09:07 AM
|- - jamescanvin   QUOTE (Richard Trigaux @ Sep 3 2005, 07:07 PM...   Sep 5 2005, 12:13 AM
- - Richard Trigaux   A rather interesting prospective explanation of th...   Sep 3 2005, 10:07 AM
- - remcook   some people seem to agree and applied for funding ...   Sep 3 2005, 10:18 AM
- - The Messenger   Richard's proposed test of the Pioneer Anomaly...   Sep 3 2005, 05:00 PM
- - Richard Trigaux   Messenger, my idea was intended to detect a gravi...   Sep 4 2005, 07:03 AM
- - Richard Trigaux   The LISA observatory project will use three test m...   Sep 5 2005, 08:57 AM
- - The Messenger   All of these approaches use assumptions we should ...   Sep 5 2005, 04:28 PM
|- - jamescanvin   Heading off topic but... QUOTE (The Messenger ...   Sep 6 2005, 12:17 AM
|- - The Messenger   QUOTE (jamescanvin @ Sep 5 2005, 05:17 PM)Hea...   Sep 6 2005, 05:53 AM
- - Richard Trigaux   Thanks jamescanvin for the image and the info it c...   Sep 6 2005, 06:37 AM
|- - jamescanvin   QUOTE (Richard Trigaux @ Sep 6 2005, 04:37 PM...   Sep 7 2005, 12:27 AM
|- - Richard Trigaux   QUOTE (jamescanvin @ Sep 7 2005, 12:27 AM)Yes...   Sep 7 2005, 05:42 AM
- - dvandorn   Once again, I'm asking a question that I proba...   Sep 7 2005, 07:36 AM
|- - Richard Trigaux   QUOTE (dvandorn @ Sep 7 2005, 07:36 AM)Does a...   Sep 7 2005, 10:28 AM
|- - The Messenger   QUOTE (Richard Trigaux @ Sep 7 2005, 03:28 AM...   Sep 8 2005, 06:21 PM
|- - Richard Trigaux   QUOTE (The Messenger @ Sep 8 2005, 06:21 PM)I...   Sep 9 2005, 07:21 AM
|- - The Messenger   QUOTE (Richard Trigaux @ Sep 9 2005, 12:21 AM...   Sep 12 2005, 01:49 PM
|- - Richard Trigaux   QUOTE (The Messenger @ Sep 12 2005, 01:49 PM)...   Sep 12 2005, 02:23 PM
|- - The Messenger   QUOTE (Richard Trigaux @ Sep 12 2005, 07:23 A...   Sep 12 2005, 06:56 PM
|- - Richard Trigaux   QUOTE (The Messenger @ Sep 12 2005, 06:56 PM)...   Sep 13 2005, 10:15 AM
|- - ljk4-1   QUOTE (Richard Trigaux @ Sep 13 2005, 05:15 A...   Sep 13 2005, 01:17 PM
- - edstrick   I'd have to check, but I think the Apollo 17 i...   Sep 7 2005, 08:22 AM
|- - Bob Shaw   QUOTE (edstrick @ Sep 7 2005, 09:22 AM)The in...   Sep 7 2005, 09:42 AM
||- - dvandorn   QUOTE (Bob Shaw @ Sep 7 2005, 04:42 AM)Oooh, ...   Sep 7 2005, 06:33 PM
||- - Bob Shaw   QUOTE (dvandorn @ Sep 7 2005, 07:33 PM)Oh, th...   Sep 7 2005, 08:47 PM
|- - dvandorn   QUOTE (edstrick @ Sep 7 2005, 03:22 AM)I...   Sep 7 2005, 06:41 PM
- - edstrick   When the gravimeter was proposed, selected and des...   Sep 7 2005, 10:38 AM
|- - Richard Trigaux   QUOTE (edstrick @ Sep 7 2005, 10:38 AM)When t...   Sep 7 2005, 02:38 PM
- - edstrick   "From what I understand, though, even with th...   Sep 8 2005, 10:49 AM
- - edstrick   It has been hoped that cosmic sources of gravitati...   Sep 9 2005, 07:45 AM
|- - Richard Trigaux   QUOTE (edstrick @ Sep 9 2005, 07:45 AM)As far...   Sep 9 2005, 08:17 AM
- - The Messenger   Suggestions, by anyone, of engineering on this sca...   Sep 13 2005, 04:16 PM
|- - Richard Trigaux   QUOTE (The Messenger @ Sep 13 2005, 04:16 PM)...   Sep 13 2005, 06:06 PM
- - The Messenger   Returning to the Pioneer Anomally: You may or may...   Sep 14 2005, 03:31 PM
|- - Richard Trigaux   Messenger, yes the Earth does have a "gravita...   Sep 14 2005, 03:46 PM
|- - ljk4-1   http://www.issi.unibe.ch/teams/Pioneer/ The Pione...   Oct 3 2005, 04:46 AM
- - edstrick   ljk4-1: "...The Pioneer Explorer Collaboratio...   Oct 3 2005, 07:15 AM
- - Richard Trigaux   Thanks ljk4-1 for your interesting contribution. A...   Oct 3 2005, 08:15 AM
- - deglr6328   sooooo did the planetary soc. get the data or what...   Oct 3 2005, 09:53 AM
|- - elakdawalla   QUOTE (deglr6328 @ Oct 3 2005, 02:53 AM)soooo...   Nov 10 2005, 01:29 AM
|- - ljk4-1   QUOTE (elakdawalla @ Nov 9 2005, 08:29 PM) We...   Nov 10 2005, 02:33 PM
|- - elakdawalla   QUOTE (ljk4-1 @ Nov 10 2005, 07:33 AM)De...   Nov 10 2005, 04:46 PM
- - edstrick   <grin> by "anomaly" I mean an ord...   Oct 3 2005, 09:57 AM
|- - Richard Trigaux   QUOTE (edstrick @ Oct 3 2005, 09:57 AM)<gr...   Oct 3 2005, 12:40 PM
- - edstrick   Aliens?... I thought it was the CIA and FBI.... or...   Oct 4 2005, 06:27 AM
|- - Richard Trigaux   QUOTE (edstrick @ Oct 4 2005, 06:27 AM)Aliens...   Oct 4 2005, 07:37 AM
- - edstrick   You know what the problem is with make-believe par...   Oct 4 2005, 10:51 AM
|- - Richard Trigaux   QUOTE (edstrick @ Oct 4 2005, 10:51 AM)You kn...   Oct 4 2005, 04:41 PM
|- - ljk4-1   Astrophysics, abstract astro-ph/0504367 From: Gary...   Oct 4 2005, 07:35 PM
|- - ljk4-1   Paper: astro-ph/0506281 replaced with revised ve...   Oct 26 2005, 02:08 PM
|- - ljk4-1   Paper (*cross-listing*): gr-qc/0511026 Date: Sun...   Nov 9 2005, 04:32 PM
- - Myran   Calculations using the 'MOND' theory (Modi...   Nov 9 2005, 09:10 PM
- - Richard Trigaux   I wonder if we could do any theory of any kind, ad...   Nov 9 2005, 09:21 PM
- - mike   That's what a theory is.   Nov 9 2005, 09:42 PM
- - Myran   QUOTE Richard Trigaux said: I wonder if we could d...   Nov 10 2005, 05:21 AM
- - lyford   Call me old fashioned, but I am a bit wary of jett...   Nov 10 2005, 06:41 AM
|- - The Messenger   QUOTE (lyford @ Nov 9 2005, 11:41 PM)Call me ...   Nov 10 2005, 04:44 PM
|- - lyford   QUOTE (The Messenger @ Nov 10 2005, 08:44 AM)...   Nov 10 2005, 10:06 PM
|- - ljk4-1   Astrophysics, abstract astro-ph/0505310 From: Mic...   Dec 20 2005, 04:05 PM
|- - ljk4-1   General Relativity and Quantum Cosmology, abstract...   Jan 3 2006, 02:31 AM
|- - tfisher   I just read through the last paper linked. They...   Jan 3 2006, 07:10 AM
|- - ljk4-1   Paper: astro-ph/0504367 Date (v1): Sun, 17 Apr 20...   Jan 4 2006, 06:18 PM
- - tasp   I bet it is not as simple as this, but I will pos...   Jan 5 2006, 04:14 AM
|- - mchan   QUOTE (tasp @ Jan 4 2006, 08:14 PM)Any possib...   Jan 5 2006, 06:06 AM
|- - ugordan   QUOTE (mchan @ Jan 5 2006, 07:06 AM)One probl...   Jan 5 2006, 08:52 AM
|- - Bob Shaw   QUOTE (ugordan @ Jan 5 2006, 09:52 AM)Wasn...   Jan 5 2006, 01:16 PM
|- - ljk4-1   Can New Horizons participate in this experiment? ...   Jan 5 2006, 02:22 PM
|- - djellison   QUOTE (ljk4-1 @ Jan 5 2006, 02:22 PM)Can...   Jan 5 2006, 02:43 PM
|- - ugordan   QUOTE (djellison @ Jan 5 2006, 03:43 PM)That...   Jan 5 2006, 02:50 PM
- - tasp   If an objection to putting a Voyager into a slow s...   Jan 5 2006, 02:45 PM
- - djellison   Damn good point actually UG - hadnt thought of tha...   Jan 5 2006, 02:58 PM
- - ugordan   QUOTE (djellison @ Jan 5 2006, 03:58 PM)Then ...   Jan 5 2006, 03:05 PM
- - NMRguy   QUOTE (Alan Stern @ Feb 23 2005, 09:20 AM)Yes...   Jan 5 2006, 05:19 PM
|- - AlexBlackwell   QUOTE (NMRguy @ Jan 5 2006, 05:19 PM)Alan add...   Jan 5 2006, 05:56 PM
- - tty   QUOTE (ugordan @ Jan 5 2006, 05:05 PM)Might h...   Jan 5 2006, 06:47 PM
3 Pages V   1 2 3 >


Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 28th March 2024 - 04:14 PM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member.