"The Spacecraft Flyby Mystery" - Is Dark Matter the Culprit or is There a New Physics ...

Daily Galaxy ^ | 8/3/10 | Casey Kazan

[LibWhacker]

When scientists send their spacecraft across the universe, they save fuel by performing “slingshot fly-bys”. This is where, rather than firing up the thrusters, the craft changes its trajectory by harnessing the enormous gravitational pull of a planet. However, this trick has had an unexpected side-effect: it seems to produce a change in speed that no one, since it was first discovered in the early 1990's, can account for.

Experts are intrigued by the fact that while the acceleration is tiny and has no significant effect on NASA missions, it holds great interest because no explanation based on conventional physics and understanding has been found. The effect is so persistent that it could indicate some physics not considered in previous attempts to explain the motions of bodies in the universe.

In 1998, for example, NASA's NEAR Shoemaker spacecraft had its speed boosted by an additional 13.5 millimetres per second. There are many examples of this, but no explanation – which raises the tantalizing possibility that it could be a sign that a whole new branch of physics is waiting to be discovered.

Mysteriously, four spacecraft that flew past the Earth have each displayed unexpected anomalies in their motions. These enigmas join the so-called "Pioneer anomaly" as hints that unexplained forces may appear to act on spacecraft. The anomalous acceleration, resulting from a pull about 10 billion times smaller than the acceleration we feel from Earth's gravitational pull, was confirmed through detailed analysis of radio data from Pioneer 10, Pioneer 11 and Ulysses spacecraft as they hurtled out of the solar system, which seemed to experience a tiny but unexplained constant acceleration toward the sun.

Jet Propulsion Laboratory astronomer John Anderson and his colleagues — who originally helped uncover the Pioneer anomaly — have studied five deep-space probes — Galileo to Jupiter, the NEAR mission to the asteroid Eros, the Rosetta probe to a comet, Cassini to Saturn, and the MESSENGER craft to Mercury. Each spacecraft flew past the our planet to either gain or lose orbital energy in their quests to reach their eventual targets. (Galileo made two flybys.) In five of the six flybys, the scientists have confirmed anomalies.

JPL researcher Anderson, first saw the effect in 1980, but waited until he had accumulated data over the next 15 years, before he could easily dismiss it as the result of systematic errors. "Like a lot of problems in astronomy, many years of observation are needed," Anderson said.

Another researcher, Michael Nieto of Los Alamos, has long been interested in the possibility that gravity works differently on antimatter than on the familiar matter that makes up our everyday world. This led him to consider how well we understand gravity's influence on normal matter and whether studies of the motions of comets or spacecraft could be used to identify any deviations from the expected influence of gravity.

"I am feeling both humble and perplexed by this," said Anderson, who is now working as a retiree. "There is something very strange going on with spacecraft motions. We have no convincing explanation for either the Pioneer anomaly or the flyby anomaly." The one probe that did not confirm an anomaly was MESSENGER, the spacecraft approached the Earth at about latitude 31 degrees north and receded from the Earth at about latitude 32 degrees south.

The five other flybys involved flights whose incoming and outgoing trajectories were asymmetrical with each other in terms of their orientation with Earth's equator, which "suggests that the anomaly is related to Earth's rotation," Anderson told the Times Online. As to whether these new anomalies are linked with the Pioneer anomaly, "I would be very surprised if we have discovered two independent spacecraft anomalies," Anderson told SPACE.com. "I suspect they are connected, but I really do not know."

"Another thing in common between the Pioneer and these flybys is what you would call an unbound orbit around a central body," Anderson said. "For instance, the Pioneers are flying out of the solar system — they're not bound to their central body, the sun. For the other flybys, the Earth is the central body. These kinds of orbits just don't occur very often in nature — it could be when you get into an unbound orbit around a central body, something goes on that's not in our standard models."

Scientists were hoping to gain more insight into the anomaly when the Rosetta spacecraft swung by Earth on Nov. 13 2009 to pick up a gravitational boost for its journey to rendezvous with a comet in 2014.

However, in a major disappointment – which had deepened the mystery — the Rosetta spacecraft did not experience the flyby anomaly during this swingby of Earth in 2009, even though the same spacecraft did experience the anomaly when it flew by Earth 2005, but didn’t in 2007.

“It’s a mystery as to what is happening with these gravity events,” said Trevor Morley, lead flight dynamics specialist working on Rosetta. “Some studies have looked for answers in new interpretations of current physics. If this proves correct, it would be absolutely ground-breaking news.”

Several ideas have been proposed in an attempt to explain why the anomaly occurs, ranging from tidal effects of the near-Earth environment, atmospheric drag, or the pressure of radiation emitted or reflected by the Earth, to much more extreme possibilities, such as dark matter, dark energy or previously unseen variations in General Relativity.

Anderson and colleagues are even looking at the possibility that Earth’s rotation may be distorting space-time more than expected, and affecting nearby spacecraft. But there is as yet no explanation how this could happen.

Stephen L. Adler of the Institute for Advanced Study, Princeton, thinks that the universe's "missing" dark matter might be culprit that's messing around with our robotic explorers. Alder suggests that the Earth may be passing through "clouds" of WIMPs -elusive Weakly Interacting Massive Particles (WIMPS) that have been theorized to contain large quantities of matter, hence a large proportion of the dark matter in our universe- giving some weight to the idea that dark matter may be contained in the volume of space surrounding Earth. As spacecraft orbiting Earth passes through this dark matter ring, perhaps there will be some complex interaction causing this sudden change in acceleration.

[arthurus]

know how things work

[arthurus]

ridiculous

[TalonDJ]

A similar story, by the otherwise nutcase Richard Hoagland:

'otherwise'? That story is total crap too. He predicates the entire convoluted logic train on claiming the solid boosters could not have been more efficient than expected when they certainly could have. As with most nutjobbery he does not bother offer real logic to counter that one premise and instead piles his arguments on other areas to distract the reader from that lacking. There is absolutely nothing at that link to disprove the supposition that the rocket's engines worked better than expected. He simply said that could not have been it and goes on to gush over unrelated half truths and nonsense.

[DrC]

“They explain and predict the orbits of artificial down to centimeters per day, or very small fractions of a millimeter per second, in the order of 0.005 mm/sec.”

I don’t doubt this is true, but how come police radar guns can only measure speed +/- a couple of MPH? Call me easily impressed, but I’m just amazed they can figure out the speed of a spaceship a bazillion miles away with that kind of accuracy.

[DrC]

“The global warming guys didn’t need to wait 15 years, or to confirm anything.”

Why waste 15 precious years when the answer has been pre-determined. Didn’t you hear? We’re DOOMED unless we start following Al Gore’s prescriptions yesterday.

[SunkenCiv]

Thanks LibWhacker!

the craft changes its trajectory by harnessing the enormous gravitational pull of a planet... an unexpected side-effect: it seems to produce a change in speed that no one, since it was first discovered in the early 1990's, can account for... while the acceleration is tiny and has no significant effect on NASA missions... no explanation based on conventional physics and understanding has been found. The effect is so persistent that it could indicate some physics not considered in previous attempts to explain the motions of bodies in the universe. In 1998, for example, NASA's NEAR Shoemaker spacecraft had its speed boosted by an additional 13.5 millimetres per second. There are many examples of this, but no explanation -- which raises the tantalizing possibility that it could be a sign that a whole new branch of physics is waiting to be discovered. Mysteriously, four spacecraft that flew past the Earth have each displayed unexpected anomalies in their motions.

It's almost as if physical reality doesn't conform to 17th century ideas, egad!

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[LibWhacker]

The cops probably could do it — if NASA built them $10 million scientific-quality handmade custom radar guns that were continuously calibrated.

[Scythian]

Ya, I could spell check it, agreed, but I use IE instead of firefox, just can’t break the habit ...

[Lonesome in Massachussets]

Police radar cost about $1000, are hand held and have observation intervals of a couple seconds and produce reasonable real-time estimates. They are subject other sources of error, included unmodeled target accelerations and effects due to the target motion not being aligned with the radar line of sight.

Satellite orbits are developed using many thousands of independent observations by multimillion dollar sensors positioned all over the globe, processed off line using large computers and sophisticated algorithms. They really are not comparable.

[tophat9000]

I wonder because times slows down the faster you go I wonder if that extra 13mm per second in not seen from the space craft perspective

[Jack Hydrazine]

It’s the on-board gyros that are probably causing the slight acceleration. They impart their own torsion field as they spin.

[Yo-Yo]

With Hoagland it's always about the Hyperdimensional Physics.

[DrC]

“Satellite orbits are developed using many thousands of independent observations by multimillion dollar sensors positioned all over the globe, processed off line using large computers and sophisticated algorithms.”

So I infer it is triangulation to the Nth degree that permits such precision?

Memo to Self: do not let Barack Obama know about this capability, else he will direct GPS satellites to catch speeders all across America and use the revenue from fines to help bankroll the growing welfare state.

[Yo-Yo]

Or interaction between the onboard gyro torsion field and the Earth's (or other planet's) torsion field.

From the article:

The five other flybys involved flights whose incoming and outgoing trajectories were asymmetrical with each other in terms of their orientation with Earth's equator, which "suggests that the anomaly is related to Earth's rotation," Anderson told the Times Online. As to whether these new anomalies are linked with the Pioneer anomaly, "I would be very surprised if we have discovered two independent spacecraft anomalies," Anderson told SPACE.com. "I suspect they are connected, but I really do not know."

[Jack Hydrazine]

Is it me or do these astrophysicists sound as dumb as a box of rocks? I guess they never received the memo on torsion fields or how the rotating bodies like planets and gyros might interact with one another.

[Lonesome in Massachussets]

Orbits are determined by the method of least squares. The technique was developed by Lagrange and Gauss in the late 18th Century for determination of the orbits of comets and asteroids (and it can be applied to planets as well).

http://en.wikipedia.org/wiki/Least_squares

If you read the wiki article, in the application of non linear least squares, the numerical values of the partial derives are your “model”, gravity, drag, radiation pressure, etc. The problem is that they work soooo well for satellites and well but not quite as well for space craft in grazing orbits. Since the partial derives are the model, the “laws of physics” the problem is to figure out a set of partial derives that work for satellites and grazing orbits. Merely fitting parameters by adding convenient terms is unsatisfactory because the numbers fit a theoretical model, and fudging means abandoning a well accepted and proven model.

Orbit determination is the classical non-linear least squares problem. I actually “taught myself” the method from the book by White, Mueller and Bates on a plane ride from Boston to Anchorage.

http://www.amazon.com/Fundamentals-Astrodynamics-Roger-R-Bate/dp/0486600610

It is really quite easy to apply with modern computers.

[samtheman]

In five of the six flybys, the scientists have confirmed anomalies.

If it happens all the time -- or nearly all the time-- it's not an "anomaly" anymore.