Posted on 07/24/2012 3:42:38 AM PDT by neverdem
It’s been a bad year to bet against Albert Einstein.
In the spring physicists had to withdraw a sensational report that the subatomic particles known as neutrinos were going faster than light, Einstein’s cosmic speed limit; they discovered they had plugged in a cable wrong.
Now scientists from NASA’s Jet Propulsion Laboratory have reported that they have explained one of the great mysteries of the space age, one that loomed for 30 years as a threat to the credibility of Einsteinian gravity.
The story starts with the Pioneer 10 and 11 space probes, which went past Jupiter and Saturn in the late 1970s and now are on their way out of the solar system. In the 1980s it became apparent that a mysterious force was slowing them down a little more than should have been expected from gravity of the Sun and planets..
Was there an unknown planet or asteroid out there tugging on the spacecraft? Was it drag from interplanetary gas or dust? Something weird about the spacecraft? Or was something wrong in our calculation of gravity out there in the dark?
That last explanation would have been big news indeed. Much of what we know about the universe — for example, the existence of dark matter, which seems to swaddle and shape the galaxies, and of dark energy, which seems to be speeding up the expansion of the universe — comes from presuming that Einstein’s General Theory of Relativity, which describes gravity as the warping of space-time geometry — is correct over cosmic distances.
General relativity has passed every test on Earth. Without correcting for it, GPS systems would not work. But some theorists have suggested that if gravity behaved differently over large distances from what Einstein thought, it would relieve astronomers of the embarrassing need to posit...
(Excerpt) Read more at nytimes.com ...
Not sure if it's really the scientists that seem to want to do this (discredit Einstein), or those in the media, looking for a big story. A little like taking down Nixon, during Watergate.
What did Albert know, and when did he know it?
You didn’t like the answer?
Science is not an attempt to disprove God. Science is an attempt by the most successful religion in the history of the universe to understand God’s creation.
Christianity is the rational religion and is responsible for creating all of the current scientific disciplines.
What an odd point of view for you to take.
Could very well be spatial anomalies. I would check the Trellium D cladding and confirm it is in multimode at 125mm. Biggest mistake is going single mode.
Screws up the core.
My point of view has always been odd. Not unusual for me to think outside of the “consensus” or the “collective”. Just the way I am wired.
Reminds me of one of my favorite Steven Wright jokes: “If you’re driving your car at the speed of light and you turn on your headlights, what happens?”
Apparently, you slow down.
Maybe if they tried Inverse Polarity ! (that seems to fix everything)
Individual liberty, personal responsibility and faith in a Divine supreme being works fabulously in mundane day to day society while unpredictable results-determined subatomic activities allow—as per Schrodinger--the first man observing the wave collapse to arbitrarily determine the properties of the latest reality—these observers of course, belong to the atheist ranks demanded by Leftist academia since Niels Bohr successfully banished Einstein's, Newton's, Galileo's, Copernicus's etc etc God from Physics...the "scientific" passing of the torch, as it were, to Freud, Darwin and Marx, of "empirically proved" moral relativism which falsely and evilly established the "justness" of politically imposed Leftist infallibility...as such currently the so-called "God Particle" is desperately to be discovered and disingenuously dissected so as to ideologically and politically reduce the term to simple, "particle.""
The beginning of knowledge is to admit you know noting...........
Certainly if you have the technology for a light speed automobile you will have the technology for tachyon headlights—the question is would they illuminate where you are going or where you have been?
So, next time I’m stuck in the mud all I have to do is turn on my headlights...............and wait a million years........I’m gonna need a bigger battery...........
No need to insult people you are responding to.
wow- they canb detext pressure that small? (or the change from it?)
That’s pretty amazing
It also means it will eventuall slow the craft down and stop it.
Does anyone know what the lifetime of the power supply is?
No truer statement, in my humble opinion.
Study Finds Heat is Source of 'Pioneer Anomaly'
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
July 17, 2012
The unexpected slowing of NASA's Pioneer 10 and 11 spacecraft - the so-called "Pioneer Anomaly" - turns out to be due to the slight, but detectable effect of heat pushing back on the spacecraft, according to a recent paper. The heat emanates from electrical current flowing through instruments and the thermoelectric power supply. The results were published on June 12 in the journal Physical Review Letters.
"The effect is something like when you're driving a car and the photons from your headlights are pushing you backward," said Slava Turyshev, the paper's lead author at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "It is very subtle."
Launched in 1972 and 1973 respectively, Pioneer 10 and 11 are on an outward trajectory from our sun. In the early 1980s, navigators saw a deceleration on the two spacecraft, in the direction back toward the sun, as the spacecraft were approaching Saturn. They dismissed it as the effect of dribbles of leftover propellant still in the fuel lines after controllers had cut off the propellant.
But by 1998, as the spacecraft kept traveling on their journey and were over 8 billion miles (13 billion kilometers) away from the sun, a group of scientists led by John Anderson of JPL realized there was an actual deceleration of about 300 inches per day squared (0.9 nanometers per second squared). They raised the possibility that this could be some new type of physics that contradicted Einstein's general theory of relativity.
In 2004, Turyshev decided to start gathering records stored all over the country and analyze the data to see if he could definitively figure out the source of the deceleration. In part, he and colleagues were contemplating a deep space physics mission to investigate the anomaly, and he wanted to be sure there was one before asking NASA for a spacecraft.
He and colleagues went searching for Doppler data, the pattern of data communicated back to Earth from the spacecraft, and telemetry data, the housekeeping data sent back from the spacecraft. At the time these two Pioneers were launched, data were still being stored on punch cards. But Turyshev and colleagues were able to copy digitized files from the computer of JPL navigators who have helped steer the Pioneer spacecraft since the 1970s.
They also found over a dozen of boxes of magnetic tapes stored under a staircase at JPL and received files from the National Space Science Data Center at NASA Goddard Space Flight Center, Greenbelt, Md., and worked with NASA Ames Research Center, Moffett Field, Calif., to save some of their boxes of magnetic optical tapes.
He collected more than 43 gigabytes of data, which may not seem like a lot now, but is quite a lot of data for the 1970s. He also managed to save a vintage tape machine that was about to be discarded, so he could play the magnetic tapes.
The effort was a labor of love for Turyshev and others. The Planetary Society sent out appeals to its members to help fund the data recovery effort. NASA later also provided funding. In the process, a programmer in Canada, Viktor Toth, heard about the effort and contacted Turyshev. He helped Turyshev create a program that could read the telemetry tapes and clean up the old data.
They saw that what was happening to Pioneer wasn't happening to other spacecraft, mostly because of the way the spacecraft were built. For example, the Voyager spacecraft are less sensitive to the effect seen on Pioneer, because its thrusters align it along three axes, whereas the Pioneer spacecraft rely on spinning to stay stable.
With all the data newly available, Turyshev and colleagues were able to calculate the heat put out by the electrical subsystems and the decay of plutonium in the Pioneer power sources, which matched the anomalous acceleration seen on both Pioneers.
"The story is finding its conclusion because it turns out that standard physics prevail," Turyshev said. "While of course it would've been exciting to discover a new kind of physics, we did solve a mystery."
Pioneer 10 and 11 were managed by NASA Ames Research Center, Moffett Field, Calif. Pioneer 10's last signal was received on Earth in January 2003. Pioneer 11's last signal was received in November 1995. JPL is a division of the California Institute of Technology in Pasadena.
Maybe at the time scales involved, the power module (nuclear, which was assisted by photocells when the craft was near the sun, but no more) will have long petered out before directional emission of infrared photons could significantly slow the craft let alone stop it.
I’m cudgeling my brain without success to remember the name of the little physics toy that had an assembly of two to four vanes, painted white on one side and black on the other, mounted to pivot in a nearly evacuated glass bulb. Sunlight would make the vane assembly turn as the black side of the vanes became warmer than the white side. And yet it wasn’t light pressure that achieved this, but differential between how the residual gas in the bulb was warmed and set in motion at the surfaces of the vanes.
Well you do have to know enough to understand that gaining more knowledge is helpful and important.
Or if you have to make a sudden stop, just put the lights on.
You mean writing music, or making little self-memos so you don't forget things? I'm going with the latter, because it helps me retain what little knowledge I have.
That's a Radiometer.
Maybe I need Cliff’s Notes for Dummies...........
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