Skip to comments.Mystery Tug on Spacecraft Is Einstein’s ‘I Told You So’
Posted on 07/24/2012 3:42:38 AM PDT by neverdem
Its 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, Einsteins cosmic speed limit; they discovered they had plugged in a cable wrong.
Now scientists from NASAs 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 Einsteins 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 ...
Oops!.....forgot the pic!............
Without the Times' Science Tuesday section, I would not have found the story.
Nope, that's just what was in the official Starfleet reports. The truth is there's a massive destructive force headed for earth and we have to go back in time to save the whales.
Well at least you enjoy using your computer and being on the internet. ;)
Or... the white surface reflected 'light', and the black surface absorbed light. In a sense, repulsion and attraction. The gas near the white surface would tend to expand due to the additional 'reflected heat', adding 'repulsion' to the mix.
Maybe it's a combination of things, instead of one thing.
Sounds just as reasonable as...
Swamp gas from a weather balloon was trapped in a thermal pocket and reflected the light from Venus.
Please look right here.
A radiometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Generally, the term radiometer denotes an infrared radiation detector, yet it also includes detectors operating on any electromagnetic wavelength.
A common example is the Crookes radiometer, an early-model device wherein a rotor (having vanes which are dark on one side, and light on the other) in a partial vacuum spins when exposed to light. A common myth (one originally held even by Crookes) is that the momentum of the absorbed light on the black faces makes the radiometer operate. If this were true however, the radiometer would spin away from the non-black faces, since the photons bouncing off those faces impart even more momentum than the photons absorbed on the black faces. Follow the link below for an in-depth explanation of the principles behind a Crookes radiometer.
The Nichols radiometer operates on a different principle and is more sensitive than the Crookes type.
A microwave radiometer operates in the microwave wavelengths. The radiometer contains argon gas to enable it to rotate.
The MEMS radiometer, invented by Patrick Jankowiak, can operate on the principles of Nichols or Crooke and can operate over a wide spectrum of wavelength and particle energy levels.
(I learn something new every day.)
All I can say is the scientists did the math and it made sense once they did. The effect is extremely tiny of course compared with the craft’s rapid velocity. They are talking about a few hundred feet lagged during a period when the craft went millions of miles into space.
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