Hi borman, welcome to the BAUT forum.
I liked your input on this topic (which many of us are watching, but few are saying much about).

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Forming opinions as we speak

Thank you for your welcome, antoniseb.

Usually parallels become apparent in retrospect after they become established by observation. As all the hard data will need to await orbital insertion of MESSENGER, we are temporarily constrained to consider the less likely prospect of parallels.

Before the development of Gneral Relativity, the perihelion advance of Mercury was an outstanding anomaly. The usual direction to follow is to use standard physics as it was understood at the time to suggest a resolution to the anomaly. At the time, the best classical solution was to invoke the existence of a planet, called Vulcan, which could be totally responsible for the perihelion advance. However, no such planet was discovered and the new idea of General Relativity which represented an improvement upon Newtonian gravity theory postdicted the anomaly well.

Now we have a new anomaly during the MESSENGER flyby of Mercury. Again, following the usual direction, one resorts to physics as we know it today to offer a solution to the anomaly. In this case, it was offered that there is a surface over-density near periapsis that could account for up to 95% of it. Perhaps there are additional surface anoamlies to get the remaining 5%. To retain a flavor of historical perspective, let us refer to the anomaly as the Vulcan surface gravity anomaly. We do not yet have the data to rule this possiblity out yet. Surface anomalies of this magnitude will not just evaporate in the few years until orbital insertion. So if it is not seen later by MESSENGER, it likely never existed and the initial hypothesis stands falsified. Then something else is responsible for the flyby anomaly.

This brings up the possibility that whatever physics is responsible for the flyby anomalies seen to occur during the gap that includes periapsis at Earth might also be in play everywhere including Rosetta at Mars and MESSENGER at Mercury. There is great advantage in discovering the physics involved if one can study it in differing environments to see how different parameters contribute their weight in establishing the anomaly.

The new Anderson paper should be seen as a follow up to the earlier energy transfer paper. Comparison of errors of theoretical values to measured values range from 2% (NEAR) to 300% (MESSENGER). Being within an order of magnitude really does represent progress. But still, it should be allowed that this is a first approximation and even better fits can be attained by further considering values that were not included in the original simple formula. As a rough guide, one should review the appendix B in the earlier energy transfer paper with its GM values for the other bodies and write out the equations of the new paper for each of the moon, sun and Jupiter with respect to periapsis to each at the Earth event radius and the cosines to each to see if the additions make the predictons of the formula even tighter, maybe improving the theoretical result by another decimal or so. The team needs to do a little more preliminary work in order to help shine a light upon the prospective underlying cause.

Finding the anomaly at Mercury would be quite useful in sorting out what weights to give various parameters in the Earth equations that can not be well realized because we do not yet have non-Earth values to compare against that would suggest the weighting. For example, the new equation suggests rotation may be an important factor in deriving the constant of proportionality. However, calculation of GR frame dragging corrections show the pure GR correction to be too small to be measured and it would be drowned out by the background in any event. Also there is a minor theoretical point that GR corrections use powers of v/c where v is total velocity where the present anomaly is proportional only to the fraction of velocity that is excess hyperbolic. Using total velocity in the new formula gives very wrong answers compared to measurements. But it still remains a possibility that frame dragging, as a parameter, may figure partially into the anomaly's cause, but not in the way normally used by GR.

It is here where values of the anomaly at Mercury can be very useful. Mercury itself rotates mcu slower than Earth. On the other hand, the sun is much closer and although its rotation rate is slower than Earth's, it has a much greater radius. By comparing the values at Mercury with those at Earth, one can get a quantitative feel for the magnitude of contribution of various parameters as they weigh in to make the anomaly expose itself.

Once the physics of the anomaly is understood, one look to see if the same physics can explain other outstanding anomalies. It makes some sense to consider that if the circumstances occur to establish the anomaly at any scale, it will be forced to show itself. On the larger scales there are the anomalies of the Pioneer anomaly and the Dark Matter anomaly. At the local scale, there may be the Alais anomaly that NASA was interrested in with regard to the flyby anomaly. At the somewhat smaller scale there are the anomalies associated with speeding up or slowing down the spinning of superconductors that have had a London Moment established in them with papers written by Tajmar and Podkletnov respectively. At the smallest scale there is the mass anomaly measured for Cooper pairs in Niobium superconductors, normaly known as the Tate Anomaly. Normally QM is good to 11 decimals, but this error, reported in 1986, is in the 4th decimal. The anomaly may be forced to expose itself even at the low temperatures where solid Helium and pinning fluxes serve to create a context for NCRI, or non classical rotational inertia. Some of these instances of anomalies can be quite strong compared to the classical frame dragging values derived from GR. Tajmar's experiments suggest 30 orders of magnitude difference, although the first theory attempt to describe the anomaly as gravitomagnetism has been considered falsified by the author, Tajmar. The anomaly at low temperatures is not strictly associated with superconductivity since it persists up to temperatures in excess of 30K which is well above the critical temperature of 7K for Niobium. This may make it a pseudogap phenomonon more often associated with high temperature superconductors. The common denominator seems to be associated with establishing a frame of reference where some portion of the velocity becomes that which is beyond being bound to the system whether the difference is in the particles such as hyperbolic velocity excess of the craft or the acceleration of the frame relative to the frictionless particles, such as cranking the London Moment frame relative to the Cooper Pairs. When these things happen, the anomaly shows itself.

That is good to know. From the article, we could not ascertain whether the model using a gravity resulted in greater gravitational braking or less: excess hyperbolic velocity clearly means the effective orbital velocity of the probe was not reduced as much as expected. I needed to hear that, thanks!

Whoa! I have been expecting the gravity measurements to be very quirky near Mercury, but not that far out of wack! (Although I realize this is a relative error measurement, so the known constraints are tight.)

The difficulties I have run into here, (aside from not having my arms completely around the navigational calculations), is that in many descent profiles and such; there are three sigma variance accepted into the calculations, minimizing the difference between the expected and observed results. If there is a related family of anomalies skewing the data, it will be necessary to backtrack through the data and sort our 'more realistic' solution.

Don't limit yourself to the investigation of known anomalies. I suggest some head-to-head examination of Huygens descent profile with the ESA PI's. Mercury will reveal anomalies, but to find the proper constraints, it will also be necessary to reexamine Ganymede, Europa and a whole slew of Cassini and Huygens radio/gravitational data.

...If and only if the researchers trust their instrumentation at least as much as they trust the theories they are constrained by. It is possible that the 'patch effects' being backed in to the Gravity G probe data are not patch effects at all, but yet another manifestation of the unexpected.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

Here is the NASA-Messenger page showing the orbital flights: http://messenger.jhuapl.edu/whereis/index.php

If Messenger is coming in from ‘behind’ Venus and Mercury in its ‘slow down’ slingshot maneuvers, there may be one other effect on this maneuver (since it is happening closer into the Sun) that may be skewing the slingshot effect. This may ostensibly be from a ‘transfer of momentum’ from the very large mass of the Sun’s spin, which acts in a tidal fashion on the Messenger orbital slingshot effect. Has this been calculated into the apparent anomaly? The Sun has a very large mass, and its spin at the equator is perhaps large enough to cause this effect. I had mentioned this transfer of momentum effect on an earlier post (Caution: ATM!) regarding Mercury’s precession, but don’t have any numbers to work with on these Messenger anomalies.* It may also be the effect Anderson found recently on an Earth flyby, which he thought might be related to Earth’s spin, which could be related?

I just thought to leave this idea on the table, though I cannot provide any calculations at this time to support the hypothesis, that angular momentum transfer from the Sun, or other bodies (in a GR frame dragging fashion, as borman suggests), has effect on flybys.

*(In the earlier post link is another link which goes to a page where the actual numbers of solar momentum transfer are shown – where it says: " per http://arxiv.org/PS_cache/gr-qc/pdf/0507/0507041.pdf (this link no longer works), in which the value for solar momentum is: L_sun = 1.9E+41 m^2 kg s^-1 ")

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Credibility is simply incredible... sometimes even to me.
disclaimer

Hi Jerry

To avoid confusion, it should be separated between what is observed in the Earth flybys and the proposal that MESSENGER had a Mercury flyby. Prior to the conference, the MESSENGER team presented an abstract of what was expected from the data before the flyby actually occured. But after the flyby they found their expectations were not met and suggestions of a surface gravity anomaly were offered to explain the data. The information about this was presented in another thread here where the report was issued by Emily from the Plantery Society.

But it should be noted that the new Anderson et al paper was only available online as of March 7 which was when the congress started. It is entirely possible that the MESSENGER team did not yet know of the Anderson et al paper or that any of the Anderson team knew of the data about MESSENGER anomaly. Emily did not report whether the question of Anderson flyby anomaly was even brought up in any discussions immediately after the update of the Mercury flyby. The actual details regarding the angles will have to await a paper published showing the details of the flyby. As regards the Earth flyby anomaly, it is the case that there is additional positive deltaV on the outgoing velocity, not loss of ingoing velocity. This is observed whether the assist is to speed up or slow down the craft which is to say whether the craft passed outside or inside the orbit to steal momentum from the planet or lose momentum respectively. According to normally understood physics there should be no deltaV.

We will not have precise values for MESSENGER at Mercury until the details are published. The 300% error is in regard to MESSENGER at Earth in the Anderson paper. The estimated observed value is very small and the theoretical estimate is also very small, but it is three times the measured value. The absolute quantity of fractions of millimeters per sec of DeltaV is small. Sometimes the theoretical value is greater than the observed value, sometimes smaller, but there is a good relation all the same. I was merely suggesting that it may be possible to increase the accuracy of the formula by paying attention to other massive bodies as well. It should be looked at.

To be sure, if the anomaly is universal in that it appears at Mars and Mercury and is not particular to Earth, one should evaluate its effect wherever there is an energy transfer where there is excess hyperbolic velocity and there is a difference in cosines.

Regarding Gravity Probe B, the data was taken in a bound orbit without any excess hyperbolic velocity. Hence this term vanishes in the formula and there would be no flyby anomaly according to the present Anderson formula. It appears that the anomalies in the GP-B data are too small to account for the flyby anomaly.

One idea that may need some research that does not resort to new physics but instead represents an intrusion of older physics into new physics might be thought of as "Newton's Revenge". Such a paper would have been written between 80 to 90 years ago that might point to a derivation of the new Anderson formula. It would follow the 1918 Thirring paper but probably not unitl the mid 1920's. If it was not written, this may have been in deference to permitting Einstien to persue his ultimate goal of making a General Relativity theory inclusive for all accelerations much like he made a comprehensive Special Theory for all velocities. Had he succeeded in this endeavor, this would have "greased the tracks" and laid the foundation for forming a unified field theory he envisioned. No one presented a convincing NoGo theorem, so he kept working at it until the end. The issue is not that all gravitational fields can be put into corresponence with an acceleration, but rather that not all accelerations can be put into correspondence with a gravitational field. As deSitter noted, covariance is not sufficient. So it remains a possibility that the totality of all accelerations can be divided into two families: those that are within the province of GR and those that are not. This later makes up "Newton's Revenge".

The 80 year old paper, if it exists, would consider the role of "Newton's Revenge" in the context of the Thirring frame dragging paper. Newton looked to the example of the rise of water in a spinning bucket to claim absolute motion. The amount of the rise is something of a problem for GR as the effect predicted and contributed by GR is many orders of magnitude smaller than what is actually observed. This has some symmetry with the present flyby anomaly problem. The actual magnitude of the DeltaV is many orders of magnitude greater than the predictions of GR. The difference is that instead of a bucket of water, one substitues a bucket of space-time. One then checks to see if order of magnitude difference is comparable to the actual measured DeltaV as compared to the GR contribution so that the major contribution to DeltaV is rather due to "Newton's Revenge".

It is tempting to consider that the string theory will have the elbow room to accomodate both families of accelerations. Right now, it is more like the blind men and the elephant where the M theory is evaluated at various limits to give either a trunk, foot or tail, but the total theory is not yet seen. The string theory will need to explain the outstanding anomalies as well as conventional physics or else it will be dead on arrival.

Hello Nutant,

In the Earth flybys, tidal effects were considered but could not account for the flyby anomaly. The contribution to the anomaly from Mercury alone would be two orders weaker than that seen at Earth. But the contribution due to the sun at Mercury would be greater than the sun's contribution at Earth. Mercury's perihelion advance has been observed better than Earth's perihelion advance.

Well, at least a resolution of the Pioneer Anomaly may be near. "Newfound Data Could Solve NASA's Great Gravity Mystery" is the title of an article posted on space.com this time last year. Turyshev, one of the scientists who first pointed out the anomaly said:
"But Turyshev remains confident that once the information is ready for analysis, the anomaly shed new secrets."

In other words, maybe Newton is wrong or may be there is some more mundane explanation-- at least we are relatively close to finding out which is the case. I thought it was kind of cool Turyshev said about Pioneer being an inadvertant gravitational experiment:

“The Pioneer spacecraft conducted the largest ever gravitational experiment that humanity attempted to test Newton’s Law, and it failed,” Turyshev told SPACE.com. “If we will identify an anomaly due to conventional physics thermal mechanism or propulsion or a combination there off, that’s a major event.”

Thanks for clarifying this. If Messenger continues to be successful, we will have plenty of data to chew on. My much less conservative approach is to dismiss the 'gross positive gravity anomaly at the point of closest approach' is an unlikely solution and urge everyone in the community to start reviewing other data for peculiarities in the current solution. That said, as a practical solution, we are a long ways from introducing new physics to the classroom. But it is important to urge this generation of student scientist to be highly skeptical.

Yes, but don't hold your breath. Thermal and other conventional mechanisms have been weighed in the past, and although they cannot be ruled out; the slope of the Pioneer acceleration is not consistent with nuclear decay rates, solar heating rates, oxidation rates and such.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

Another way to frame this, is that they could only account for 95% of the error using surface anomalies. (If adding more density to the surface would have been reasonable, why didn't they?) Either they maxed-out the reasonable surface density, or the vectors don't quite add up using surface effects.

In any case, they moved up the planned post fly-by correctional burn ~two weeks; which is an extraordinary change in a navigational plan (with minor corrections, they would only make the burn longer). It means Messenger was significantly off-course after the gravitational braking fly-by; and an interesting contrast to the New Horizons probe after the Jupiter fly-by, that required only a minor burn as scheduled.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

Jerry,
Until we have the data, it is hard to say whether the burn was harder because of navigational problems induced by the flyby or whether, being close to the sun's well, a hard burn was being planned anyways.

It is important to note that, at least for Earth flybys, Anderson said the anomaly would be too weak to be a menace to navigation. While small errors may be somewhat magnified by the sun, they may not represent a threat to navigation to insertion if only a few millimeters/sec are involved. But as we do not yet know the physics behind the anomaly, we can not yet estimate whether the environment at Mercury would produce a greater effect than that seen at Earth. Rather, if there is a greater effect at Mercury, this may help in sorting out what the physics might be in play behind the anomaly. That is why the later gravity maps of Mercury will be helpful in constraining how much any surface gravity anomalies may have figured into the recent flyby.

Speaking of Turyshev and Anderson, they wrote a paper back in 1996 about testing GR in a Mercury orbiter. I don't know how many of their suggestions were implemented in the current MESSENGER mission. After the excess hyperbolic velocity is burned off to attain orbital insertion, the flyby anomaly should vanish leaving one with just the normal GR values at that environment. Finding the normal values there would give the background against which the anomaly can be studied in retrospect. It is roughly analogous to finding the homogenous solution to a differential equation before considering the inhomogenous solutions afforded by the anomaly.

folkhemmet,
There is no promise that the flyby anomaly and the Pioneer Anomaly are the same. Nobody likes anomalies anymore than they like the measles. So it would be desireable to bring them into coincidence so as to slay as many as possible in one blow.

On the surface, as noted in papers written so far, there is the problem that the force responsible for the flyby anomaly, acting over so short a time to produce the DeltaV, appears to be around 6 orders of magnitude stronger in the flyby anomaly than in the Pioneer Anomaly. The Pioneer Anomaly stays constant over distances from 20 to 80 AU out. Unlike the gravitational force of the sun which falls off as inverse squared, the Pioneer anomaly does not get weaker with distance which makes it share some of the attributes of the Dark Matter Effect which is also observed to be inverse linear. In contrast, the flyby anomaly is in effect only for short times and short distances compared to the Pioneer Anomaly.

Still, in spite of these problems, it may possible to bring them into coincidence by according weight to some of the clues present in the main papers so far. One potentail clue in the Pioneer papers is to assign importance to the other less well known anomaly present as well, the so called spindown anomaly. The spindown anomaly may have a chance of being explained as a systematic as a slight gas leak in the jets that are used to get the craft spin stabilized. It is very small, but persistent. One might be already acustomed to the persistent loss of pressure in aerosol cans that hold oil or shaving cream. The new analysis with telemetry may help to sort out if this is a viable systematic. It is then perhaps important to see if there is a correlation between the spindown and the more famous anomaly. In connection with the more recent New Horizons mission, it has not been reported that there is either a spindown or the Pioneer Anomaly monitored in the craft event though it is spin-stabilized in its hibernation state enroute to Pluto. It has passed Jupiter and will soon pass Saturn. In contrast, one of the Pioneer craft showed evidence of the anomaly in the cruise phase between Jupiter and Saturn. It could be that New Horizons is a newer better built craft that is not as given to making gas leaks like the Pioneers and the showing of the anomaly is in the difference. The key ingredient could be the persistent acceleration, the applied dw/dt of the monitor. If the effect is relative, one does not distinguish between acceleration of the monitor or the source but only notes a change in the spin rate in one frame or the other or both.

With the flyby anomaly, one needs to understand how it is magnified, shortlived, and cutoff. The apparent role of rotation can figure with the magnitude of the effect and its cutoff by appealing to aspects of frame dragging. It is dipole and so behaves as inverse cubed. It grows great as one approaches the rotating body and falls quickly to an assymptotic low value as one recedes from the planet. A possible reason for the cutoff is that the frame dragging well is well bounded by inverse cubed law. Meanwhile, while traversing the flux lines there is a short acceleration due to the changing direction of velocity. So if there is a short time for the dw/dt while at a certain depth of the frame dragging well, it may cross several flux lines while in transit to magnify the effect relative to the million times weaker Pioneer anomaly which may not be traversing as many flux lines while maintaining the very weak but persistent dw/dt due to spindown.

Now, it is already known that there are GR corrections but these are too small to be monitored and they are associated to total velocity and not just the portion that is excess hyperbolic. How much velocity is hyperbolic depends on the frame of reference used. One is normally accustomed to just looking at the Earth's gravity field as the frame of importance for determing the excess, but if there is rotation, then there is also a frame-dragging frame.

From the earlier post one might want to consider Newton's Demon or Revenge as regards rotation of water in a bucket or rotating space-time bounded by an inversed cubed bucket and that the corrections due to GR in the rise of water are insignificant compared to what is observed. It might be that the DeltaV might be more due to Newton's contribution to the spinning bucket effect than that from GR. Getting values from other planets that may have different frame-dragging wells may help sort out if this is a viable approach or just barking up the wrong tree.

NASA was baffled by objects being drawn to the sun? Do they need a visit from Mr. Newton?

I don't get this article.

*edit* perhaps I should have read the post above this one. The summary of the OP does seem a bit lacking in explanation though, doesn't it?

Ok, well would it be absurd to hypothesize that objects in our universe are under the gravitational influences of our Local Group? The distances at that scale would make this anomaly seem like a constant given the accuracy of our instrumentation. Or, perhaps, maybe the speed difference is not due to an attraction to something but the loss of attraction to it? Sort of a tennis ball thrown from a moving vehicle type of thing? I have no idea how to do the math on something like that or even where to start. Someone tell me what's wrong with my idea, as I'm sure I'm not the first to have it.

It is well understood, what path the Messenger Probe should have ended up on after the close pass of Mercury; based upon the attraction of the sun, Mercury, and all other other planets; including relativistic corrections. The path follow by the probe was inconsistent with known orbital dynamics...unless the surface of Mercury at the point of closest approach is significantly more dense than the planet as a whole, and that is the rub: High density at a place where there is not corresponding surface feature is unlikely. That said, the remaining choices are: 1) There was a navigational error, not likely, because the probe was coasting, and carefully tracked during most of the Mercurey encounter. 2) Newtonian physics do not correctly define orbital paths, even after relativistic corrections. Researchers should be digging into this possibility with relish... whether or not it was a prior prediction of their pet model of the solar system.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

Jerry,
It may difficult to discern just why they chose to do the burn as they did. Perhaps the anomaly, surface and or flyby, may have figured into their decision. Perhaps they will explain their reasons in an eventual update at the MESSENGER site. We will have to wait and see.

idav,

There have been considerations as to whether some of these anomalies may be associated with frames external to the solar system. This is why it may remain relevant to express orbits in not only geocentric coordinates, but solar system and galactic coordinates as well.

One older paper considered the Pioneers as a Foucault pendulum in a cosmic expansion reference frame:

The "Pioneer effect" as a manifestation of the cosmic expansion in the solar system

http://lanl.arxiv.org/abs/gr-qc/9810085

There was some further discussion as to whether the magnitude of cosmic expansion could account for the magnitude of the effect. Likewise, if the Pioneers were monitoring the Dark Matter effect known to exist in our galaxy but not generally able to penetrate into the solar well by its absence in the planetary ephemeris, the craft have to be doing something special to monitor the DM effect.

In another alternative theory, there is a variation on the MOND theory that looks at the problem from the point of view of modified Inertia rather than modified gravity. There is a recent second paper by Ignatiev that considers the rare occasions where, on Earth, there is cancellation, in a particular frame, of gravitational forces to allow a very short moment where the galactic field can be monitored. From the point of view of MOND as modified interia, there is very little difference between the galactic frame and the fram of the Local Group. Read the footnote on the bottom of page 3 to understand this aspect. If modified inertia is somehow involved with the flyby anomaly or the Pioneer effect, then there should be this predicted SHLEM effect or MOND jerk at the proper Earth Latitude at the proper equinox.
First Paper: Is violation of Newton's second law possible?
http://arxiv.org/abs/gr-qc/0612159

Second Paper:
Newton's second law versus modified-inertia MOND: a test using the high-latitude effect

http://arxiv.org/abs/0802.1599

These ideas have not been ruled out as yet. Good Hunting.

I got myself to a library (see, I follow my own advice!) and was able to see the article for myself. Here are the relevant formulae:

(1) V_INF² = v*v - 2*mu/r.

Mu is G*M_Earth, and they take the value 398600.4 km³/s² for it. The INF above stands for infinity. V_INF is the velocity that the probe would have at infinity based on v and r at that moment during the flyby. There is some variation during this time because of perturbations by the Sun and Moon.

(2) (DeltaV)_INF/V_INF = (1/2)*(DeltaE)/E = K(cos(dec_i)-cos(dec_o)).

This is the red-hot equation we're looking for. The fractional change in V_INF equals one-half the fractional change in the energy which is proportial to the difference in the cosines of the declination of inbound and outbound asymptotes (dec_i and dec_o respectively) .

And what is this factor of K? They tell us in equation (3):


(3) K = 2*w_E*R_E/c = 3.099x10^-6.

w_E is the rotational rate of the Earth, R_E is the radius of the Earth and of c is just the speed of light.

The authors admit that this effect is much larger than the expected Lense-Thirring effect. So there we have it. Like Lucy, we've got some 'splainin' to do!

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Microsoft is over if you want it.

The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high.

The thing is, we are discussing an acceleration - on the order of about 100 feet an hour extra.

Utterly cool CM, and thanks for the legwork! The apparent dependance upon the rotational rate is curious, meaning it is not something I anticipated. A greater-than-anticipated Lense-Thirring effect might also be consistent with the Gravity-B probe anomalies - there is a hint, in that the 'patch' effects they are correcting for looked like frame dragging to the analysts before they backed-out calibration factors.

When you are looking for new physics, the phenomenon has to be explored from every possible angle. Is the acceleration a function of the Earth's rotation, or does the same force that 'spins' the Earth also 'spin up' the probes? Remember, the Earth's rotation rate varies, and in a non-linear way. There is also the possibility of a gravitational shear wave that is proportional to the rotational axial gradient relative to path of the probe. (In English, the earth's rotation might cause a slight delay in the gravitational effects of the sun as they pass through the earth - the horizon deltas between when the 'solar G field' enters the Earth, and when it leaves could place the probes in small troughs: The probes surf for a fraction of a second until the field potential catches up.) That may sound like gooblygoop, but it is consistent with the deltas occasionally observed in pendulums at the onset and ending of a solar eclipse.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

This is an important comment: Many, many times potential variance in gravitation fields has been written-off as atmospheric effects. (When there is no atmosphere, surface anomalies become the suspect-of-choice.) When the Messenger probe goes into orbit about Mercury, we have a real chance of constraining surface anomalies - especially now that investigators are no longer tame about reporting anomalous data.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

Its probably dark matter or dark energy...case closed :P

We may not have to wait for orbital insertion to rule out surface gravity anomalies as the cause of the deviation. A look at the MESSENGER site shows the anticipated next two flybys from the Earth perspective. Unlike all previous Earth flybys where the craft were too close during periapsis to be seen by the stations and the recent Mercury flyby where the planet obscured the view, the next two Mercury flybys will be in view of Earth monitors.

Before, it was like turning out the lights and getting the velocity values for before and after in the vicinity of periapsis but not knowing for sure how periapsis figured into the anomaly. With the second flyby we get a good view all along the deflection. In the third flyby we have around seven minutes after periapsis until the planet blocks the view.

So, if there is the same cause for the flyby anomaly at Mercury as at Earth, we will see how the velocity gain is centered around periapsis and note the profile of the accleration. If it is rather sudden, this will tend to rule out surface gravity anomalies as they should be in effect from minus to positive infinity and not be truncated in the time domain.

This may help offer another clue to what might be going on but surely it will help show what is not responsible for the anomaly. So the upcoming October 6 flyby may give sufficient data to sort out surface anomalies from the cause or give them better support depending upon the profile.

Well, any force that is centered in Mercury would likewise peak at closest approach; so while gravity anomalies may be nullified; they really can't be confirmed until the probe is in orbit and obtains gravity maps.

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jwj

It's a big universe out there...is it really unwinding, really burning out?

The "Pioneer anomaly" was showing that both pioneers’ were slowing more then predicted. Later, the other spacecrafts were having faster flybys earth.

As if to make up for lost time, the universe remembered the "pioneer anomaly" and was making up for it by keeping in tune with the mathematical model.

A second law of quantum remembering is at play with the slowdown being complemented with a speed up of later spacecraft.

Occasional mentions of the Pioneer probe anomalies prompt me to link to this old thread which we discussed some years ago. (For anyone wanting to see what folks had to say about that phenomenon, which is still occurring.)

(This is not "To Seeking" since the subject here is new and besides, I don't "To Seek" people.)

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"Insignificant molehill sometimes more important than conspicuous mountain." - Charlie Chan

Thanks for the recall. The difference is, we now have two new peculiarities: The excess velocity near the Earth of many probes and the excess acceleration/velocity of Messenger at Mercury. In addition, there is:

1) Excess heat on the surface of Enceladus - 270 deg K(?) At least 200 K, and that is the lower limit. Where is the heat coming from?

2) The black/white patterns of Iapitus extend black areas into the 'white' regions, and the black patterns are consistent with the melt of a light snowpack: The penetration of the dark regions is greatest at the equator, crater bottoms, and polar facing ridges. This is completely consistent with the dark colors representing the underlying surface, with a thin layer of subliming water-ice slowly evaporating away.

3) A much higher-than-expected rate of cosmic ray hits on New Horizons during the deep space glide to Pluto.

4) An extremely powerful supernova - very similar to a type 'Ia', but up to two magnitudes brighter.

5) The most powerful gamma ray ever observed. (Gamma rays are already difficult to model - to come up with reasonable mechanisms.)

6) Emissions from Enceladus that 'taste like comet' - I would like more details, but the comets we have 'tasted' are rich in organics and clays.

I'm not trying to tie all of this together, only drawing attention to the unpredicted marvels we are seeing. How much more will the great scopes and current generation of planetary explorers reveal? What a terrible time to be scaling back on planned planetary probes!

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jwj

It's a big universe out there...is it really unwinding, really burning out?

I've said it before! If everything out there was "as predicted", there would be no reason to go!

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Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson

"quantum remembering"?

A superposition of states of remembering and forgetting.

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Microsoft is over if you want it.

The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high.

To be sure, any surface gravity anoamlies that may be present on Mercury will await later mapping after orbital insertion and any weight they may have contributed to the flyby anomaly can be assessed at that time.

It is the time interval over which the anomaly shows itself that points to the heart of the problem. With the second flyby, we get a front row seat to see just how short the time interval is. With the Earth flybys, there was an extended period either side of periapsis duirng which the anomaly showed itself. There was no indication in the Dopplers of a gradual onset or gradual decline of a force that one might expect if it were gravitational. Rather one had the ingoing piece and the outgoing piece with only one way to put them together, but the ends would not match up. This gives the appearance of a discontinuity. It may mean there was a spike just at periapsis which is inconsisitent with known surface gravity anomalies. It would be like there was a mountain of lead that spontaneously appeared just a few milliseconds prior to periapsis only to have the mountain suddenly vanish a few milliseconds later after periapsis.

It should be kept in mind that the reality of a force, mysterious or not, has not been established in connection with the anomaly. One is normally accustomed to attributing the action of a classical force to account for changes in velocity. However unusual, it may also occur as a result of a change of reference where some values did not remain invarient during the transformation. Einstein did not include among his "gedanken" experiments an elevator with excess hyperbolic velocity. The spacecraft during gravity assist having excess hyperbolic velocity represent a real experiment to test this situation for which there was no "gedanken" experiment.

The distinction between a re-orientation and a force could well be described by the somewhat cryptic reuslts Podkletnov got when he smashed Cooper pairs into a target and noticed an induced Allais effect at some distance in a number of different pendulla where the bobs had differeing masses. Surprisingly they all deflected equally. If the travelling disturbance had been a force in any classical sense, then the smaller bobs would have been deflected more while larger bobs would have deflected less in the same beam of disturbance. Instead, they all deflected the same angle. Meanwhile no force was monitored in non-penulla, meaning walls, bricks, or anything attached or fixed to the Earth's frame. Pendulla have some degree of freedom in the Earth frame which is how they trace a path with respect to rotation. Spacecraft are ideal as monitors since they are in freefall in all three dimensions.

As a re-orientation, the pendulla or spacecraft did not feel any force, but which way is North or Up got rotated a bit and the part that was not fixed to a frame stayed in line with the new orientation according to Newton's laws that objects moving in the straightest line will continue to do so unless operated upon by a force. If you were riding upon one of the pendullum bobs during the travelling disturbance, you would note the change of direction in unison of your bob along with all the others but would feel no force pushing you into the new direction.

There is no certainty that a re-orientation is at the root of the flyby anomaly, but if it is discovered that the time interval is very short over which the anomaly operates, this will severly constrain the nature of whatever force might be involved without hurting the re-orientation option. To sort this out, one would mount a variety of pendulla with different mass bobs on a craft with excess hyperbolic velocity to see if they all deflect equally at periapsis.

Major/minor correction: I stated that there was an earlier-than-planned correction to the Messenger's orbital path after the Mercury flyby. The correction I am referring to was after the Venus gravitational braking flyby, not the Mercury flyby. To the best of my knowledge, mission controllers have never said why the correction was a ~week before scheduled and shortly after the flyby.

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jwj

It's a big universe out there...is it really unwinding, really burning out?