Talk:Perihelion and aphelion

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I don't know whether this un-redirect is required or not. But one thing that I can say: either apsis and periapsis need there own pages, or apsis needs to be seriously rewritten. Because it's extremely confusing in its current form. — Gopher65talk 22:44, 8 August 2014 (UTC)

Well that was my reason for providing this article. Someone had found it necessary to provide a link within the Apsis article to simple:Perihelion! Obviously this article needs a referral to Apsis and clearly the maths only needs to be in one place. But the Apsis article is still trying to do too much—in particular, many people are only interested in solar orbits and the -helion and -gee terms are far more widely used. Chris55 (talk) 10:26, 10 August 2014 (UTC)
I would advocate that this article be moved to the title Perihelion and aphelion with redirects from both Perihelion and Aphelion. The only thing from the current aphelion article that needs to be moved into this one is the Greek etymology.
I'd be happy with that.
I would also advocate moving to this article the entire apsis sections Apsis#Perihelion and aphelion of the Earth and Apsis#Planetary perihelion and aphelion, but if you try to do that you may tread on some toes at the aphelion article. (talk) 20:09, 3 September 2014 (UTC)
I think you mean the Apsis article. But your caution may be justified. Let's do one at a time. Chris55 (talk) 12:39, 4 September 2014 (UTC)

Glaring contradiction[edit]

According to the text: "The perihelion is the point in the orbit of a planet, asteroid, comet or other star-orbiting body where it is nearest to its star." But then look at the image:

1. Planet at aphelion. 2. Planet at perihelion. 3. Star.

If you draw a vertical line through the star, the two points of intersection with the orbit are both closer than the point marked as perihelion. Obviously, either the definition or the image is wrong. (Presumably the image: the star is not at the focus of the ellipse.) 2602:306:CEAE:E60:940E:7689:8DC5:2704 (talk) 17:30, 24 September 2015 (UTC)

It's not a contradiction, just a very poor diagram. The "ellipse" is more like an oval and badly exaggerated. In fact the difference between perihelion and aphelion is less than 10% for most of the planets which doesn't help to make the point either. A better diagram is badly needed! Chris55 (talk) 20:32, 26 September 2015 (UTC)
Ok, I've put a somewhat better picture there. It's still exaggerated but at least the focus is in approximately the correct position and you can see that your objection no longer holds. Chris55 (talk) 22:21, 26 September 2015 (UTC)
In fact it's perfectly clear even without the exaggeration. So I've now scaled it to approximate to the earth's orbit. (The sizes of the bodies are not to scale.) Does anyone think it needs the exaggeration? Chris55 (talk) 09:53, 27 September 2015 (UTC)