Posted on 02/09/2002 6:34:49 PM PST by blam
Mysterious force holds back Nasa probe in deep space
By Robert Matthews, Science Correspondent
(Filed: 10/02/2002)
A SPACE probe launched 30 years ago has come under the influence of a force that has baffled scientists and could rewrite the laws of physics.
Researchers say Pioneer 10, which took the first close-up pictures of Jupiter before leaving our solar system in 1983, is being pulled back to the sun by an unknown force. The effect shows no sign of getting weaker as the spacecraft travels deeper into space, and scientists are considering the possibility that the probe has revealed a new force of nature.
Dr Philip Laing, a member of the research team tracking the craft, said: "We have examined every mechanism and theory we can think of and so far nothing works.
"If the effect is real, it will have a big impact on cosmology and spacecraft navigation," said Dr Laing, of the Aerospace Corporation of California.
Pioneer 10 was launched by Nasa on March 2 1972, and with Pioneer 11, its twin, revolutionised astronomy with detailed images of Jupiter and Saturn. In June 1983, Pioneer 10 passed Pluto, the most distant planet in our solar system.
Both probes are now travelling at 27,000mph towards stars that they will encounter several million years from now. Scientists are continuing to monitor signals from Pioneer 10, which is more than seven billion miles from Earth.
Research to be published shortly in The Physical Review, a leading physics journal, will show that the speed of the two probes is being changed by about 6 mph per century - a barely-perceptible effect about 10 billion times weaker than gravity.
Scientists initially suspected that gas escaping from tiny rocket motors aboard the probes, or heat leaking from their nuclear power plants might be responsible. Both have now been ruled out. The team says no current theories explain why the force stays constant: all the most plausible forces, from gravity to the effect of solar radiation, decrease rapidly with distance.
The bizarre behaviour has also eliminated the possibility that the two probes are being affected by the gravitational pull of unknown planets beyond the solar system.
Assertions by some scientists that the force is due to a quirk in the Pioneer probes have also been discounted by the discovery that the effect seems to be affecting Galileo and Ulysses, two other space probes still in the solar system. Data from these two probes suggests the force is of the same strength as that found for the Pioneers.
Dr Duncan Steel, a space scientist at Salford University, says even such a weak force could have huge effects on a cosmic scale. "It might alter the number of comets that come towards us over millions of years, which would have consequences for life on Earth. It also raises the question of whether we know enough about the law of gravity."
Until 1988, Pioneer 10 was the most remote object made by man - a distinction now held by Voyager 1. Should Pioneer 10 make contact with alien life, it carries a gold-plated aluminium plaque on which the figures of a man and woman are shown to scale, along with a map showing its origin that Nasa calls "the cosmic equivalent of a message in a bottle".
Journal reference: Nature (vol 415, p 297)
Also Casimir effect (quantum zero point fluctuations)--
small scale: (meter) Eotvos Experment (reported meter-scale secondary (repulsive anomaly) effects dependent on material (M vs Z; spin characteristics?); 100 years of repeated experiment - inconclusive; (larger scale experiments: now using corner-cube reflectors of Apollo on the moon)
solar system scale: (10 A.U.) (attractive anomaly) Pioneer anomaly (this thread)
cosmic scale: (20 billion light year)(repulsive); cosmological constant
Thats what I'm thinking as well.
second guess, totally different. correct conclusions, reason for slow down is from the presence of onboard radio transmitters, the propogation itself, they are somehow tied in with gravity.
/layman's guesses
"Kepten, there's a Hand on the ship!!
These things keep us humble.
There is a little bit that we understand and a lot that we don't.
I sincerely doubt that any physicist or astronomer knows the exact value of the gravitational constant out to 10 decimal places.
They also don't know the exact mass of the spacecraft - there may be residual fuel onboard that wasn't used but isn't accounted for in the mass calculation.
Maybe there is something subtle we don't know yet about light, gravity, and space. This is exciting news, we may be on the brink of a new understanding of where we live.
This data will have to be watched for a long while! Perhaps a deep space interferometry experiment or long paseline ring laser gyro would shed some (delayed) light on the "matter".
I'm not referring to deceleration. In referring to a slight acceleration in the direction of motion away from Earth and the solar system. I remember reading about this a few years ago. Maybe as little as two years ago. The people monitoring the Voyagers and the Pioneers said the space craft were speeding away from the the Sun at a faster rate than predicted. And these scientists had no explanation for the phenomenon. Some proposed explanations included:
i) The pressure of sunlight on the vehicles.
ii) Possibly some sort of gas leaking from the space craft slighly accelerating them.
iii) The expansion of space -- thus effecting the measured speed of the space craft.
iv) Measurement errors.
v) Something effecting the radio signals from the space craft.
Now they say the vehicles are inexplicably slowing down. Albeit, very slightly.
Well, if it is Hillary's fatass, and if they are aliens, then they will be overjoyed at finally finding their fat-assed goddess.
It's clear and simple, and can be understood by the people.
Its possible that the spacecrafts trajectory continues to remain constant, but the radio signals are being affected.
As the spacecraft approach the Oort cloud, the transmissions might be getting interference from an electrical discharge.
Just speculation.
"Based on 50 years of accumulated observations of the motions of galaxies and the expansion of the universe, most astronomers believe that as much as 90 percent of the stuff constituting the universe may be objects or particles that cannot be seen. In other words, most of the universe's matter does not radiate--it provides no glow that we can detect in the electromagnetic spectrum.
"First posited some 60 years ago by astronomer Fritz Zwicky, this so-called missing matter was believed to reside within clusters of galaxies. Nowadays we prefer to call the missing mass 'dark matter,' for it is the light, not the matter, that is missing."
Perhaps the answer to that mysterious force lies HERE.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.