- LRK -
Back in October I received an e-mail from Natalie Wolchover who was working on an article for Popular Science magazine about the Pioneer Anomaly. We exchanged a couple of e-mails and now a pleasant surprise, it is on-line at POPSCI. I think you will appreciate what she reports. It is three web pages and has some Pioneer 10 and 11 images and even one of the Pioneer 10/11 Telemetry Display on my Mac Quadra 950 showing the very low signal level.
- LRK -
Enough of my feeling good about being in print. The article is really about what Dr. Slava Turyshev and Viktor Toth have been working on and that is where the story really gets interesting. Enjoy the read.
- LRK -
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The Pioneer Anomaly, a 30-Year-Old Cosmic Mystery, May Be Resolved At Last
http://www.popsci.com/
http://www.popsci.com/
What is the mystery force slowing down the Pioneer spacecraft? Do we finally know the answer?
By Natalie Wolchover Posted 12.15.2010 at 11:00 amThirty years ago, NASA scientists noticed that two of their spacecraft, Pioneer 10 and Pioneer 11, were veering off course slightly, as if subject to a mysterious, unknown force. In 1998, the wider scientific community got wind of that veering—termed the Pioneer anomaly—and took aim at it with incessant, mind-blowingly detailed scrutiny that has since raised it to the physics equivalent of cult status. Now, though, after spawning close to 1000 academic papers, numerous international conferences, and many entire scientific careers, this beloved cosmic mystery may be on its way out.
Slava Turyshev, a scientist at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., and Viktor Toth, a Canada-based software developer, plan to publish the results of their strikingly comprehensive new analysis of the Pioneer anomaly in the next few months. Their work is likely to bring a conclusion to one of the longest and most tumultuous detective stories of modern astrophysics.
snip
http://www.popsci.com/
http://www.popsci.com/
------------------------------
When you finish with Natalie's article you might be interested in looking at some of the comments.
Some good, some so, so.
An interesting blog about her article is found at DISCOVER Blogs/ Cosmic Variance
- LRK -
------------------------------
Farewell, Pioneer Anomaly?
http://blogs.discovermagazine.
by Sean
Here’s an excellent article in Popular Science about the Pioneer anomaly. (Via Dan Vergano on Twitter.) The Pioneer spacecraft, launched in the early 1970’s, have been moseying through the outer regions of the Solar System for quite some time now. But a careful analysis of tracking data indicated that the acceleration of the two spacecraft didn’t quite match what we’d expect from gravity; there appears to be an anomalous acceleration, nearly constant over time and pointing toward the Sun. Many new-physics explanations have been proposed, but it’s always been a difficult scenario to master; it’s very hard to imagine a new force that would account for the Pioneer data but not also show up in observations of the outer planets. (The Voyager spacecraft aren’t as useful for this purpose, as they are guided by tiny thrusters that overwhelm the signal, while the Pioneers float freely and are pointed using gyroscopes.)
The most likely explanation has always been that we didn’t completely understand the spacecraft, or the tracking system. Indeed, it’s been recognized for a while that a small imbalance in how the spacecraft radiated heat could account for the acceleration — but that imbalance didn’t seem to be supported by what we knew about the vessels. That may be changing, however. The Popular Science article is a little cagey, but it mentions a new and unprecedentedly thorough analysis by Viktor Toth and Slava Turshyev that should be coming out soon. Here is as much as they would let on:
snip
------------------------------
Even though Slava and Viktor have not published the one coming up on their definitive stand you can get all the background you need by reading their last publication. You can read on-line or a 165 page PDF file where at the end you can look at 428 references or 427 on-line at http://relativity.
- LRK -
------------------------------
snip
------------------------------
It has been a fun ride and I have really enjoyed having played a small part in the quest for an answer to the Pioneer Anomaly.
To watch the data come in from a spacecraft that has traveled for 11 hours through space is something you don't get to do everyday.
- LRK -
------------------------------
http://web.archive.org/web/
30 YEARS FROM LAUNCH AT CAPE CANAVERAL ON MARCH 2, 2002, PIONEER 10 DATA WAS RECEIVED AT MADRID
GOLDSTONE On 1 March 2002, DSS 14 transmitted an uplink, and two no-op commands at 200 kw to the spacecraft.
MADRID
22 hours later, from 79.4 AU, DSS 63 acquired the downlink on time at -183 dbm. After peaking the signal to -178.5 dbm, they locked the telemetry at 16 bps with SNR of -0.5 db.
ARICEBO
SETI Institute also acquired the same signal at Puerto Rico. SETI has been using Pioneer 10 as a reference signal.
http://web.archive.org/web/
Project Phoenix has been observing Pioneer 10 at Arecibo in Puerto Rico through the auspices of the SETI Institute. The signal from Pioneer 10 was also picked up at Arecibo on 2 March 2002.
The last telemetered data from the University of Iowa cosmic ray instrument were as follows: 2 March 2002 (39 minutes of clean data) (r = 79.83 AU) 27 April 2002 (33 minutes of clean data) (r = 80.22 AU)
snip
------------------------------
We no longer hear from Pioneer 10 and 11. The mission is over and the computer space has been cleared of all hardware.
Mixed emotions when you have to pull out the old cables to make way for an office space. No more raised computer floor. :-(
-------------------
Pioneer 10 now silent. Hardware coming out. See Pictures.
http://lkellogg.vttoth.com/
-------------------
Voyagers I and II continue to transmit from deep space.
http://voyager.jpl.nasa.gov/
Well I sort of got off the topic of Natalie's article on the Pioneer Anomaly.
All I can say is, "Thanks for the memory Natalie."
- LRK -
Thanks for looking up with me.
- LRK -
Web Site: http://lkellogg.vttoth.com/
BlogSpot: http://kelloggserialreports.
Newsletter: https://news.altair.com/
Farewell, Pioneer Anomaly?
http://blogs.discovermagazine.
by Sean
Here’s an excellent article in Popular Science about the Pioneer anomaly. (Via Dan Vergano on Twitter.) The Pioneer spacecraft, launched in the early 1970’s, have been moseying through the outer regions of the Solar System for quite some time now. But a careful analysis of tracking data indicated that the acceleration of the two spacecraft didn’t quite match what we’d expect from gravity; there appears to be an anomalous acceleration, nearly constant over time and pointing toward the Sun. Many new-physics explanations have been proposed, but it’s always been a difficult scenario to master; it’s very hard to imagine a new force that would account for the Pioneer data but not also show up in observations of the outer planets. (The Voyager spacecraft aren’t as useful for this purpose, as they are guided by tiny thrusters that overwhelm the signal, while the Pioneers float freely and are pointed using gyroscopes.)
The most likely explanation has always been that we didn’t completely understand the spacecraft, or the tracking system. Indeed, it’s been recognized for a while that a small imbalance in how the spacecraft radiated heat could account for the acceleration — but that imbalance didn’t seem to be supported by what we knew about the vessels. That may be changing, however. The Popular Science article is a little cagey, but it mentions a new and unprecedentedly thorough analysis by Viktor Toth and Slava Turshyev that should be coming out soon. Here is as much as they would let on:
snip
------------------------------
- LRK -
------------------------------
Slava G. Turyshev and Viktor T. Toth,
"The Pioneer Anomaly",
Living Rev. Relativity 13, (2010), 4. URL (cited on 12/19/2010):
http://www.livingreviews.org/
or
http://arxiv.org/abs/1001.3686
The Pioneer Anomaly
"The Pioneer Anomaly",
Living Rev. Relativity 13, (2010), 4. URL (cited on 12/19/2010):
http://www.livingreviews.org/
or
http://arxiv.org/abs/1001.3686
The Pioneer Anomaly
(Submitted on 20 Jan 2010 (v1), last revised 19 Aug 2010 (this version, v2))
snip
------------------------------
To watch the data come in from a spacecraft that has traveled for 11 hours through space is something you don't get to do everyday.
- LRK -
------------------------------
http://web.archive.org/web/
30 YEARS FROM LAUNCH AT CAPE CANAVERAL ON MARCH 2, 2002, PIONEER 10 DATA WAS RECEIVED AT MADRID
GOLDSTONE On 1 March 2002, DSS 14 transmitted an uplink, and two no-op commands at 200 kw to the spacecraft. MADRID
22 hours later, from 79.4 AU, DSS 63 acquired the downlink on time at -183 dbm. After peaking the signal to -178.5 dbm, they locked the telemetry at 16 bps with SNR of -0.5 db.
ARICEBO
SETI Institute also acquired the same signal at Puerto Rico. SETI has been using Pioneer 10 as a reference signal.
PIONEER SPACECRAFT CONDITIONS
Very cold with most temperature readings at the bottom of their scale. Bus voltage about 26 volts (nominal is 28). Uplink received from DSS 14 at -131.7 dbm. Two commands received, both confirmed as executed. Geiger Tube Telescope Instrument on, and data received.http://web.archive.org/web/
Project Phoenix has been observing Pioneer 10 at Arecibo in Puerto Rico through the auspices of the SETI Institute. The signal from Pioneer 10 was also picked up at Arecibo on 2 March 2002.
The last telemetered data from the University of Iowa cosmic ray instrument were as follows: 2 March 2002 (39 minutes of clean data) (r = 79.83 AU) 27 April 2002 (33 minutes of clean data) (r = 80.22 AU)
snip
------------------------------
We no longer hear from Pioneer 10 and 11. The mission is over and the computer space has been cleared of all hardware.
Mixed emotions when you have to pull out the old cables to make way for an office space. No more raised computer floor. :-(
-------------------
Pioneer 10 now silent. Hardware coming out. See Pictures.
http://lkellogg.vttoth.com/
-------------------
Voyagers I and II continue to transmit from deep space.
http://voyager.jpl.nasa.gov/
Well I sort of got off the topic of Natalie's article on the Pioneer Anomaly.
All I can say is, "Thanks for the memory Natalie."
Thanks for looking up with me.
- LRK -
Web Site: http://lkellogg.vttoth.com/
BlogSpot: http://kelloggserialreports.
Newsletter: https://news.altair.com/
===========================================
WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK
==============================
WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK
==============================
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