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I am removing the large block of text added on 23 April 2009 by the anonymous editor 65.50.23.77 for many reasons. First, it is a copyright violation because most of the text comes from Einstein's Nemesis#1: DI Herculis apsidal motion puzzle solution by Professor Joe Nahhas and the remainder comes from a dead link also by Nahhas. Second, it is a fringe theory because it states that Einstein's general relativity is wrong. Third, it is much too technical for an article in an encyclopedia. Fourth, it overpowers the rest of the article, which is concerned with Newtonian apsidal precession, that is, that due to the perturbations of other planets. — Joe Kress ( talk) 02:12, 31 May 2009 (UTC)
That chart at the bottom of this page about the "effect" of apsidal precession on the seasons can't possibly be right--at least, the reality is too much more complicated to make that chart useful. The chart implies--or requires--that the earth's axis maintains the same orientation as apsidal precession proceeds. Except this isn't true. Both axial and apsidal precession would have the exact same, and indistinguishable, "effect" on the seasons, but it is really incorrect to talk about either without mentioning the other. — Preceding unsigned comment added by 72.8.56.170 ( talk) 17:30, 17 July 2012 (UTC)
How do the two precession types not have the same effect on the seasons? They both change the length of a given season, and they both change the length of time between the equinox and periapsis. — Preceding unsigned comment added by 207.198.105.24 ( talk) 01:29, 16 July 2015 (UTC)
JamesGibbsMcLean (
talk) 03:44, 20 March 2015 (UTC)
could someone please use math-environments and type in the formulas correctly? it's not usable the way it is right now. thanks! -- Kondephy ( talk) 18:27, 12 November 2013 (UTC)
The formulas (and explanations of course) should be added. See for example this paper: precession of orbits about an oblate planet (Greenberg, Astronomical Journal, vol. 86, June 1981, p. 912-914) -- Kondephy ( talk) 13:11, 19 November 2013 (UTC)
I added Skorekeep's actual words from his (her?) edit summary (which he could/should have done himself). It's still confusing and seems to be making a point which is off-topic and dubious: that Newton's gravity model is pitted against something that appears to be a mathematical method. That's a nonsequitur because it's an apples and oranges comparison. Both Newton's model and perturbation theory are off topic. If they're actually on topic, that's not clear by the wording chosen.
Also, that Newton's model can't handle more than three bodies is just wrong. It can't make a neat little equation for more than 2 bodies, but the model doesn't break down as the new wording suggests. I'm also pretty sure perturbation theory (a mathematical method, not a model) can't do that either. The problem with Newton's model is that it doesn't produce the observed apside rotations, but the passage is unclear as to how that's related to perturbation theory or even what perturbation theory is.
In it's original state, the section was vague, it's meaning was inscrutable. Passages with inscrutable meanings have no meaning and must be removed unless someone can clarify the meaning. In it's new state, the passage is now dubious as well as uncited making its removal imperative.
So, PLEASE, if anyone wants to mention how perturbation theory actually applies, and why it's better, and what it's better than, then please please please adjust the wording to solve those problems, don't just make a reactionary reversion.
I'll leave the current (vague, dubious, uncited, etc.) wording up for a few days to allow someone to fix it (even though "dubious+uncited" is grounds for immediate removal). I'm not an expert and I cant do the fixing. I can only note the logical errors, on/off topic, lack of citation, etc. I'm also knowledgeable enough to detect some dubiosity (as above). If someone can't try to address the problems within a few days, I can only remove the material again and it will be the burden (see WP:burden) of someone who want's to replace it to include a reliable ref at that time (as well as restate it more clearly).
98.216.243.204 ( talk) 03:13, 9 May 2016 (UTC)
Good point. I implemented it. It still has the "method vs. model" apples v. oranges comparison though (retaining its inscrutability) which needs to be addressed. Also, if I got it wrong (misinterpreted the matter) please correct it. 98.216.243.204 ( talk) 09:38, 9 May 2016 (UTC)
Hi there
Martijn Meijering,
I reverted (mostly) the 12 May edits for "Vague" and "Dubious"...
I should have said "inscrutable" instead of "vague".
The text:
"...the rate of apsidal precession calculated via Newton's theorem of revolving orbits is not as accurate as it is in a three-body model using the unmodified inverse-square law. Such calculations can be done either numerically or using methods such as
perturbation theory."
It's hard to see there how a "three-body model" is relevant, or even if it's a thing at all. A three-body isn't a model, it's a situation to which models are applied. I can't figure out what the text meant to say there. It's inscrutable, which is worse than "vague" because if something is "vague" then one at least has an idea of what it's about. I'm not trying to keep you from saying something (whatever it is you're trying to get across), I just want to make sure that whatever we say (as editors) is understandable at least (after that it should be not-dubious and possibly cited too of course).
98.216.243.204 ( talk) 23:30, 20 May 2016 (UTC)
If a model doesn't make reliable predictions, it's not valid. If another model comes after it and it makes more reliable predictions and people come to know that and come to use the new model more than the first, then the first model is "superseded". If Newton's model tries to put forward an inverse-cubed force, and that force is found to not be present, then the model is quite invalid. Actually, "invalid" is more apt than "superseded" because "superseded" implies the first model was actually used at one point, which doesn't seem to be the case here.
All scientists mess around with many ideas that turn out to not work. They think one up. They test it in their minds to see if it makes any kind of sense (i.e. they try to think up something that would falsify it right off the bat). Then they test it for real, or write it down so others can test it. Surely Newton tried many models (in his mind at least) before he came upon F=GMm/r2 (his big success). It's no big deal for a model to be later seen as invalid or to be superseded. It's just part of the process.
In any case, whatever we say must first be understandable. Then, it must be not-dubious. Then if it's at all unexpected, it must cited. I removed the text because it was inscrutable. No one could even tell if it was dubious or not because its meaning couldn't be clearly discerned.
98.216.243.204 ( talk) 23:26, 21 May 2016 (UTC)
Nahhas theory is correct The editor who removed it is clueless It is a peer reviewed article. Here is a first Proof "Newton's time dependent equation" synthesis of relativity and quantum mechanics By Roger Anderton "Nahhas' Newtonian derivation of Mercury's perihelion by Roger Anderton
Newton's equation is solved wrong for 350 years The Correct solution produces Einstein's relativity theory numbers
The editor need be not editing — Preceding unsigned comment added by 24.96.60.139 ( talk) 03:53, 2 July 2018 (UTC)
Shouldn't there be a table of observed and calculated precession rates of solar system bodies and contributions of different causes? Or a pointer to such table if one can be found elsewhere. — Preceding unsigned comment added by 213.216.243.75 ( talk) 06:13, 11 June 2019 (UTC)
Hi. It's frustrated me to come here and find relativistic precession, along with the statement (surely true) that tidal effects are orders of magnitude more significant, without any citation or reference to them. It is those tidal (J2) effects I'd like to know about and understand. Maybe after that the secondary and tertiary nuances but sheesh we're missing the forest for the leaves here. — Preceding unsigned comment added by 174.216.12.220 ( talk) 10:56, 3 August 2019 (UTC)
[I moved this from above the title box down to where it belongs, added the title. SkoreKeep ( talk) 17:18, 3 August 2019 (UTC)]
In the "History" section it says that Ptolemy didn't take into account lunar apsidal precession, this is probably a misquote from somewhere that claims that Ptolemy didn't take into acount the solar apsidal precession. In fact Ptolemy has the apogee of the sun's orbit fixed on the ecliptic relative to the equinoxes (which he uses as a basis for his ecliptic coordinates). However, in the first lunar model inherited from Hipparchus, he has the apogee of the moon have a period of 8.85 years, approximately. The second lunar model only adds adjustments that are significant when the moon is away from the apogee. So this claim at the minimum needs a source. EricPiphany ( talk) 14:15, 17 September 2022 (UTC)
I'll add here that the number 8.88 doesn't seem to appear in the source given, only "about 9 years". EricPiphany ( talk) 14:56, 17 September 2022 (UTC)
I do find 8.8826 on the wikipedia Antikythera mechanism page, as the computed interval based off the number of teeth on the different gears (some of the gears it seems were missing so their teeth counts were calculated to reasonable amounts). EricPiphany ( talk) 15:30, 17 September 2022 (UTC)
How does 112000 apsidal and 26000 axial combine to an average of 23000?
Shouldn't it be 112000 / (112000 / 26000 + 1) = 21,101.449...? Bumy Goldson ( talk) 18:52, 10 June 2023 (UTC)