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Pioneer Anomaly Solved
First time accepted submitter gstrickler writes "After years of work recovering and analyzing old mission data and vehicle schematics, a just published analysis(Pdf) provides strong evidence for anisotropic thermal radiation being the source of the slowing of the Pioneer 10 and 11 spacecraft. The theory isn't new, but the recovered data and new analysis provide solid evidence that at least 80% of the deceleration is accounted for by anisotropic thermal radiation. Members of The Planetary Society were instrumental in recovering the data and helping fund the analysis. The lesson is, in space, it matters what direction your heat radiating surfaces point."
Was just wondering what the company have made an Anomaly out of...
Heat makes things go fast!
Err... is it the slowing of the craft, or the accelerating? Because the analysis refers to the "acceleration" of the spacecraft.
That's that, I guess.
Y'all wanna do somethin?
Sorry to self-correct - acceleration is a vector, it has both magnitude and direction. By summing all of the acceleration vectors, you get a resultant which determines the rate of change of your velocity.
Is it just my observation, or are there way too many stupid people in the world?
...you are going faster than before, eh?
Does this discovery have a relationship (however distant or inefficient) to Nuclear Lightbulb or Nuclear Photonic propulsion? https://en.wikipedia.org/wiki/Nuclear_lightbulb
The Voyager probes are getting closer to Earth! They have twitter feeds, and report the light-travel time to the Earth. If you look at the history of their tweets, you'll see they have been getting closer to Earth recently.
Well that's been solved. What now?
"First time accepted submitter gstrickler" != "at least once rejected submitter gstrickler".
FTFY
make imaginary.friends COUNT=100 VISIBLE=false
So now they know why its slowing down, can they fix the problem?
I think they should reconfigure the main deflector to emit a tachyon pulse. That usually works.
The lesson is, in space, it matters what direction your heat radiating surfaces point.
It matters in bed too.
It must have been something you assimilated. . . .
... or the Repugs bringing back Romney.
A portuguese aeronautics engineering student from Instituto Superior Técnico already figured this out way back in 2009 in his masters thesis, available here.
Slashdot, fix your code or at least hire someone who is competent at it to do it for you.
Will this effect be powerful enough to ever cause it to stop, turn around and come home? And when it does so, how much strife will it cause to Spock and Kirk?
But if heat radiation does not have mass then why should it effect it?
Does it have mass?
Troll is not a replacement for I disagree.
Or rather a confirmation of some preliminary work done years agor (2008) http://www.planetary.org/blog/article/00001400/
It is very nice to see this analysis come to a clear conclusion. There are many reasons for physicists and those who feel constrained by the laws of physics to wish for violations of known laws that have significant effects in our corner of the galaxy. But time after time mundane explanations based on known laws turn out to be right. At some point more people are going to catch that we are not going to continuously overturn accepted science. Eventually the philosophers and sociologists of science might catch on too. But maybe that is wishful thinking.
So, the reason accounting for %20 of the unknown deceleration is still a mystery? If so drop the term "solved".
I had a Crookes radiometer (http://en.wikipedia.org/wiki/Crookes_radiometer) as a kid, which demonstrated this very thing.
Umm, speaking of which...
Dark Matter. It's always Dark Matter. Except when it's Cosmic Strings. Or Quantum Boogaloos. Or Electron Roulette.
But at least it's not the Phlogiston.
It depends on the particular machine race the spacecraft runs into; If it's Beserkers, they aren't going to care about the cute bald chick. :)
The Borg on the other hand; If they look like 7of9, they can assimilate me anytime.
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Truth isn't Truth - Guliani
If I understand ion thrusters correctly (that's a big if), a big tank of neutral atoms are bombarded by electrons to knock other electrons out of orbit around those atoms, creating positive particles, which are electrostatically accelerated out a big metal screen thing and the motion of them going the opposite way makes your spaceship go the correct way.
I believe thermal radiation in this article's context means heat being turned into infrared light, that means photons going the opposite direction can have a noticeable impact on an existing spaceship in a real world text over a relatively short distance in space. I would think a gigantic atom nucleus has thousands of times more mass than a photon so ion thrusters would be pretty effective over time. Now of course the opposite "kick back" reaction is proportionate to the amount of energy you're putting into the ions and their speed is ohhhhh just a hair slower than a photon (lol) but at least we can say the theory should work in real space based on this experience.
This means it wasn't Voldemort making a Horcrux out of the Pioneer Plaque!
A> Solved
B> evidence for
brash pronouncements of a _solution_ (A) sound a lot like a hard MAYBE (B). *sigh*
FTFY
Isnt it convinent shit can have no "mass" but still have "momentum".
No rest mass, but they do have relativistic mass, m_r = h*f/c^2, where h is Planck's constant, f is photon's frequency, and c is speed of light. And they are affected by gravity, a photon emitted from a flashlight held horizontal will fall on Earth a bit. That's why gravitational lensing works.
A successful API design takes a mixture of software design and pedagogy.
All gases expand if they are released in a lower pressure environment. I wander what happens when you release a gas under pressure at high temperature in the space outside the solar system. I would guess that it accelerates as it cools down. What about the matter released by the Big Bang. Do we really need dark matter?
A spacecraft dedicated to disproving this anomally should be slingshotted out of the solar system to test this once and for all and address the reamining 20%. It could be a cheap spin-stabilized craft with a pinger and a transmitter and carefully studied thermal characteristics.
It's sort of like we're measuring a solar sail effect to the point that there is such thing as a Cd value in space.
the true cause was aliens on a nearby planet
Oh, I suppose I'd better RTF-preprint now. Just for a change.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"