Mercury perihelion precission

[Obelix]

I appologize in advance if this topic has been discussed before in this forum. If it has, I have not encountered it.

 

A "dedicated enemy of Einstein and Relativity Theory" - whom I believe some of you already know, his name is Tsolkas - has recently claimed to have explained the precission of Mercury's perihelion by the fact that the sun itself orbits around the barycentre of the solar system. He claims that nobody else, from Leverrier to nowdays, did ever take into account this fact, and that "all astronomers before...him ("Tsolkas Magnus") always considered the solar system's barycentre as essentially identical with that of the sun"!

 

It would be a waste of time to trouble you with the rediculous reasoning he uses in his "derivation" of the precission. My question is this: I can't possibly believe that such a fact realy escaped Leverrier's notice - let alone ALL astronomers to the present day. I believe that it was somehow taken into account in pre - relativity astronomy, still leaving the well known gap of 43" / century. So, does anyone know of any books/papers where the consideraton of the sun's motion around the barycentre is taken into account? Is this motion actually dealt with in the theory of perturbations caused by the planets in Mercury's motion?

[Gozzer101]

Don't they use a method of finding planets outside our solar system using this method?

 

They detect stars with a tell tale "wobble" which are in fact orbiting the solar systems centre if mass.

[mathematic]

Don't they use a method of finding planets outside our solar system using this method?

 

They detect stars with a tell tale "wobble" which are in fact orbiting the solar systems centre if mass.

 

The usual method of extra-solar planet detection is by fluctuations in light intensity due to the planet passing in front of the star.

[questionposter]

The usual method of extra-solar planet detection is by fluctuations in light intensity due to the planet passing in front of the star.

 

The Kepler telescope uses both.

Edited January 8, 2012 by questionposter

[D H]

@Obelix: Tsolkas is a crackpot. Of course astronomers account for the gravitational acceleration of the Sun toward the planets. BTW, it's "precession".

 

@Gozzer101: You are talking about Doppler spectroscopy.

 

@mathematic: There is no single "usual method". There are instead a number of different techniques used by different investigators.

 

@questionposter: No, it doesn't. The Kepler mission uses the transmit method. Confirmation by Doppler spectroscopy is done elsewhere.

[Obelix]

@Obelix: Tsolkas is a crackpot. Of course astronomers account for the gravitational acceleration of the Sun toward the planets. BTW, it's "precession".

 

I know what Tsolkas is, only too well... I've been watching him since March 1986.

 

What does "BTW" stand for?

 

Do you know of any papers on the topic (perihelion precession) that explicitly mention consideration of sun's motion relative to the barycentre?

[D H]

I've been watching him since March 1986.

This guy has been tilting after windmills and cracking pots for a quarter of a century? Goodness.

 

 

Do you know of any papers on the topic (perihelion precession) that explicitly mention consideration of sun's motion relative to the barycentre?

You'll have to go way, way back.

 

S.Newcomb, “Discussion and results of observations on transits of Mercury from 1677 to 1881”, Astr. Pap. am. Ephem. naut. Alm., 1, 367-487 (U.S. Govt. Printing Office, Washington, D.C., 1882).

 

I suspect that Newcomb did not "explicitly mention consideration of sun's motion relative to the barycentre." There is no need to do so. A heliocentric frame works just fine, as does a geocentric frame. (I suspect he did the latter given that you'll often see general precession cited as a part of the overall precession of Mercury.) Use an origin other than the solar system barycenter and you'll get fictitious forces. There's nothing wrong with that so long as you account for these fictitious forces. The name for these fictitious forces in the astronomy community (and in aerospace as well) is "third body effects".

 

Why do you need to go so far back into history? Simple. This is a solved problem. Scientists don't get paid to revisit solved problems.

 

What they get paid to extend the state of the art. Here you will find plenty of references regarding modeling the solar system from the perspective of a barycentric frame and in a fully relativistic framework. All three of the leading planetary ephemerides, the DE series from JPL, the EPM series from the Institute of Applied Astronomy, and the INPOP series from the Paris Observatory, do just that.

 

 

Let's suppose that Tsolkas is right. That means that

- Astronomers and physicists from the 1800s on up to Einstein's time (and later). All of them.

- Modern astronomers who supposedly model the solar system to very high precision using a fully relativistic formulation are lying.

 

Or we could suppose that Tsolkas is wrong.

Edited January 8, 2012 by D H

[Obelix]

This guy has been tilting after windmills and cracking pots for a quarter of a century? Goodness.

 

I first encountered him in a magazine called "Periscope of Science", published in Greece since 1977 (the "Scientific Greek" you might call it). Last year it was struck by the crisis and switched publisher. I have also been writting in it, from 2007 onwards.

 

As regards Tsolkas, he had then published one of his uproarious "proofs" that "Galileo and Einstein were both wrong in claiming that bodies accelerate equally in a gravitational field, regardless of mass". All he "discovered" then (as well as innumerable times, afterwards!) was the simple fact that the relativity principle essentially has to do with a one - body problem (i.e., an IDEALIZED MODEL) whereas, in the actual universe, one needs to deal with two body problems, where the mass of both bodies has to be taken into account.

 

The said magazine is a serious one, and always mantained a high quality. Yet they made the mistake to take that article seriously ("We have been unable to spot any mistakes in it..." was their foreward). And I can ensure you, after chatting many times with the editor about it, they have CURSED the moment they chose to publish him, with all their heart! After they realized what they had done, whenever they were suspicious about anybody whose theories they were about to publish, they expressed their suspicion by saying: "What if he is another Tsolkas?"

 

Why do you need to go so far back into history? Simple. This is a solved problem. Scientists don't get paid to revisit solved problems.

 

You're very much right! But I happen to be a college tutor and students ask for details about the veracity of what they're taught. One can't just tell them: "It is a solved problem and you have to stick to it!" Now my topic is Mathematics and Relativity, whereas this falls into Celestial Mechanics. So I'm not experienced with literature.

 

Besides, sadly enough, there are people influnced by charlatans like Tsolkas. If not entirely, they may at least wonder: "What if he is right, after all?"

 

I don't want to "revisit a solved problem". I just want to show anybody asking that Sun's motion round the barycentre HAS been taken itno account. If one wants to work out details, one is welcome to do so oneself!

Edited January 9, 2012 by Obelix

[D H]

I can't help you much with that source of the data used by Einstein and others. As far as I can tell, it is that 120+ page booklet published back in 1882 by the US government printing office that is the source of the observed precession and the calculation of the portion of the precession attributable to Newtonian mechanics. Einstein's paper references this booklet, as do several other papers I happened to find. None of those papers re-performed the calculations of the parts of the precession attributable to Newtonian mechanics.

 

That Simon Newcomb could have made such a blatant mistake is ludicrous. Then again, I can't get at that paper. It's certainly not on the 'net. It's too old.

 

 

What you can find on the 'net are descriptions of how JPL, the Paris Observatory, and the Russian Institute of Applied Astronomy calculate their ephemerides. All three are now fully relativistic and do their calculations in a solar system barycenter frame. If Tsolkas is right, those groups would have found that they can't make their calculations match observations (some of which are very, very old; thousands of years old). You're a scientist: Would these groups have conspired to keep these findings hush-hush or would they have been in a race to reveal their findings to the world?