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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.

"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 ...

A pioneering team from IBM in Zurich has published single-molecule images so detailed that the type of atomic bonds between their atoms can be discerned.

why are we not getting these type of startups in Europe .... btw: Will is british

I agree, the mentality is different, it's hard to find VC funding for hardware stuff, even more so if you wanna shoot your HW into space. but there is movement, e.g. pioneers.io, they are in vienna and are actively trying to get more VC funding (in europe) for HW and other engineering startups

thanks for the link ... just read this blog ... http://pioneers.io/blog/space-race-2-0-putting-satellites-into-the-hands-of-everyone a lot of selling talk but fundamentally I agree that they have a point ... and as ACT we will face the criticism in not so long that we have not managed (nor tried hard enough) to convince ESA about the need to embrace this "new space"

nice article on Russian Mars exploration pioneers ...

denmark are the pioneers in the field

A new manufacturing process could mean improved efficiency for solar cells. The technique, which is being pioneered by researchers at the University of California, San Diego, results in "hairy" solar cells.

Doesn't really sound sexy, but this is of utmost importance for next generation grids for renewable energy.

I agree on the significance indeed - a small boost also for my favourite Desertec project ... Though their language is a bit too "grandiose": "ABB has successfully designed and developed a hybrid DC breaker after years of research, functional testing and simulation in the R&D laboratories. This breaker is a breakthrough that solves a technical challenge that has been unresolved for over a hundred years and was perhaps one the main influencers in the 'war of currents' outcome. The 'hybrid' breaker combines mechanical and power electronics switching that enables it to interrupt power flows equivalent to the output of a nuclear power station within 5 milliseconds - that's as fast as a honey bee takes per flap of its wing - and more than 30 times faster than the reaction time of an Olympic 100-meter medalist to react to the starter's gun! But its not just about speed. The challenge was to do it 'ultra-fast' with minimal operational losses and this has been achieved by combining advanced ultrafast mechanical actuators with our inhouse semiconductor IGBT valve technologies or power electronics (watch video: Hybrid HVDC Breaker - How does it work). In terms of significance, this breaker is a 'game changer'. It removes a significant stumbling block in the development of HVDC transmission grids where planning can start now. These grids will enable interconnection and load balancing between HVDC power superhighways integrating renewables and transporting bulk power across long distances with minimal losses. DC grids will enable sharing of resources like lines and converter stations that provides reliability and redundancy in a power network in an economically viable manner with minimal losses. ABB's new Hybrid HVDC breaker, in simple terms will enable the transmission system to maintain power flow even if there is a fault on one of the lines. This is a major achievement for the global R&D team in ABB who have worked for years on the challeng

In a jaw-dropping feat of engineering, electronics turn a person's thoughts into commands for a drone. Using a brain-computer interface technology pioneered by University of Minnesota biomedical engineering professor Bin He, several young people have learned to use their thoughts to steer a flying robot around a gym, making it turn, rise, dip, and even sail through a ring.

Pretty cool, so when is this going to be available for our quadrocopter?

A bit late, but it is very interesting and instructive to listen to Gordon Moore's words "It almost doubled every year (...) so I said in the next 10 years it's going to continue to double every year, we are going to go from 16 components on a chip to 16 000. Pretty wild extrapolation!". This extrapolation (exponential with only 5 initial points) is now well-known and is one of the things that changed the World, it is pretty amazing how this "wild" futuristic vision came true.

A great source is also the blog from Chris Mack (http://life.lithoguru.com/?p=451) who is a semicon pioneer and publisher of many books on the subject. He wrote an article for IEEE Spectrum on Moore's law and its future. Find it here, http://spectrum.ieee.org/semiconductors/processors/the-multiple-lives-of-moores-law

Whenever I think about moore's law and extrapolating like that I end up back at this xkcd comic https://xkcd.com/605/

In the world of mathematical tiling, news doesn't come bigger than this. In the world of bathroom tiling - I bet they're interested too. If you can cover a flat surface using only identical copies of the same shape leaving neither gaps nor overlaps, then that shape is said to tile the plane. Also only mathematicians can put the words "Pentagon", "attack", and "plane" in the same sentence...

I especially love this part of the story: "The hunt to find and classify the pentagons that can tile the plane has been a century-long mathematical quest, begun by the German mathematician Karl Reinhardt, who in 1918 discovered five types of pentagon that do tile the plane. (To clarify, he did not find five single pentagons. He discovered five classes of pentagon that can each be described by an equation. For the curious, the equations are here. And for further clarification, we are talking about convex pentagons, which are most people's understanding of a pentagon in that every corner sticks out.) Most people assumed Reinhardt had the complete list until half a century later in 1968 when R. B. Kershner found three more. Richard James brought the number of types of pentagonal tile up to nine in 1975. That same year an unlikely mathematical pioneer entered the fray: Marjorie Rice, a San Diego housewife in her 50s, who had read about James' discovery in Scientific American. An amateur mathematician, Rice developed her own notation and method and over the next few years discovered another four types of pentagon that tile the plane. In 1985 Rolf Stein found a fourteenth. Way to go!"

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 :-)

Unexplained annual variations in nuclear decay rates have been reported in recent years by a number of groups. We show that data from these experiments exhibit not only variations in time related to Earth-Sun distance, but also periodicities attributable to solar rotation. Additionally, anomalous decay rates coincident in time with a series of solar flares in December 2006 also point to a solar influence on nuclear decay rates....

can we use space to make a smart experiment to solve this riddle? e.g. sending a decay detecter on a close solar orbit and one to Pluto and then compare decay rates? or a highly elliptical trajectory and compare during peri and apoapsis?

I think it could be possible. I need to look into the details. In fact it could probably be done already with the nuclear generators on the Voyager and Pioneer and other nuclear powered probes. That is if the data are precise enough...