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This is really cool. I know one of the authors and he is a good guy... the only thing that leaves me unsatisfied is that if the whole issue is related to thermal effects one should have seen the Pioneer effect all the time and not only at about 10 AU... ...or is there some thermal process that kicked in only at this distance?

Here's an update on this theory: NASA Releases New Pioneer Anomaly Analysis "The mysterious force acting on the Pioneer spacecraft seems to be falling exponentially. That's a strong clue that on-board heat is to blame, says NASA." Heat emission 'most likely cause' of pioneer anomaly "What's more interesting is that, contrary to the original analysis conducted all those years ago, the deceleration does seem to be decelerating at an exponential rate -- just as one might expect from the radioactive decay of plutonium-238, which powers the two spacecraft. Turyshev concludes, "The most likely cause of the Pioneer anomaly is the anisotropic emission of on-board heat.""

The article came out some time ago of course and was posted here, though the story here is still well written. If you are lazy to read the rel long article, here the summary explanation: The team found that a good half of the force came from heat from the RTGs, which bounced off the back of the spacecraft antenna. The other half came from electrical heat from circuitry in the heart of the spacecraft. Most of that heat was radiated through louvers at the back of the probes, which weren't as well insulated as the rest of their bodies, further contributing to the deceleration.

"The Atomki group has produced three previous papers on their beryllium-8 experiments - conference proceedings in 2008, 2012 and 2015. The first paper claimed evidence of a new boson of mass 12 MeV, and the second described an anomaly corresponding to a 13.45-MeV boson. (The third was a preliminary version of the Physical Review Letters paper.) The first two bumps have disappeared in the latest data, collected with an improved experimental setup. "The new claim now is [a] boson with a mass of 16.7 MeV," Naviliat-Cuncic said. "But they don't say anything about what went wrong in their previous claims and why we should not take those claims seriously." One naturally wonders, he said, "Is this value that they quote now going to change in the next four years?""

"Given that for both craft electricity is supplied by a radioisotope thermoelectric generator (RTGs) powered by the heat given off by the radioactive decay of plutonium - an energy source that decays exponentially with time - Turyshev and others suggested that the extra acceleration could be caused by thermal radiation being emitted from the craft in a preferred direction. "

"After decades spent thinking, arguing, hoping, and in the words of Turyshev, "making a career off of it," these scientists' interest in the Pioneer anomaly has, understandably, accumulated psychological baggage; in the case of many of them, a cloud of emotional investment has formed around the core of objective scientific inquiry. And clouds obscure things."

165 pages about it!! http://arxiv.org/abs/1001.3686

good old Turyshev ...

MTA-Atomki A laboratory experiment in Hungary has spotted an anomaly in radioactive decay that could be the signature of a previously unknown fifth fundamental force of nature, physicists say - if the finding holds up. Would be cool, after all the high energy physics being done to verify the SM it could be extended at the other end where nobody bothered to look ;)

:-)

Well, it's not yet confirmed... That error would be worse than the magnetic moment of the muon about 10 years ago. There, it was "at least" a conflict of conventions used in the computer codes!

In a statement based on an earlier press release from the OPERA collaboration, CERN said two possible "effects" may have influenced the anomalous measurements. One of them, due to a possible faulty connection between the fiber-optic cable bringing the GPS signals to OPERA and the detector's master clock, would have caused the experiment to underestimate the neutrinos' flight time, as described in the original story. The other effect concerns an oscillator, part of OPERA's particle detector that gives its readings time stamps synchronized to GPS signals. Researchers think correcting for an error in this device would actually increase the anomaly in neutrino velocity, making the particles even speedier than the earlier measurements seemed to show. CERN's statement says OPERA scientists are studying the "potential extent of these two effects" but doesn't indicate which source of error (if either) is likely to outweigh the other. However, Lucia Votano, director of the Gran Sasso laboratory, says the "main suspicion" focuses on the optical-fiber connection. She adds that OPERA researchers deserve credit for "having tenaciously followed this particular evidence via checks completed in the last few days." The two effects will get a new round of tests in May, when the two labs are scheduled to make velocity measurements with short-pulsed beams designed to give readings much more precise than scientists have achieved so far.

Following a discussion with Kzrystof, where he came up with gravity anomaly reasons for why Dutch people are so tall. Funny to see this fact gathers scientific attention as well.

We solved this darwinian riddle years ago. They must be tall in order to find their partners above the fog and thus reproduce in the dutch weather.

Sante have a look at this ... Daniel is the TU researcher who did the study I was sending you a few years ago with Luzi - very nice and smart guy .... Luzi: now you will have difficulties in shooting :-)

Sante, Luzi have a look at this???!!!

Leo, you mean that they measured 3 years? That's not a point to criticize: since the only interaction of neutrinos with matter is the Weak Interaction (which is indeed very, very weak), it is extremely hard to get a reasonable statistic. By the same reason, it's essentially impossible to shield the experiment from the background. And this background (solar neutrinos, cosmic radiation neutrinos) is huge.

for sure a result to be taken seriously. It makes a buzz in my lab... but always be cautious with this kind of declaration, that hugely violates all physics we know and even most of the reasonable alternative theories... Remember the Pionneer anomaly for which it took almost ten years to set up that finally its a thermal effect.

still - 13 years of success is not bad!!

The effect of gravity on virtual electron-positron pairs as they propagate through space could lead to a violation of Einstein's equivalence principle, according to calculations by James Franson at the University of Maryland. While the effect would be too tiny to be measured directly using current experimental techniques, it could explain a puzzling anomaly observed during the famous SN1987 supernova of 1987.

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth-very close in astronomical terms-the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and hundreds of thousands of other galaxies towards it with a gravitational force equivalent to a million billion Suns. Lead author Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said the team found 883 galaxies, a third of which had never been seen before. "The Milky Way is very beautiful of course and it's very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it," he said. Professor Staveley-Smith said scientists have been trying to get to the bottom of the mysterious Great Attractor since major deviations from universal expansion were first discovered in the 1970s and 1980s. "We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour." The research identified several new structures that could help to explain the movement of the Milky Way, including three galaxy concentrations (named NW1, NW2 and NW3) and two new clusters (named CW1 and CW2).