Talk:equinox

Equinoces?
I could be wrong, but I think the plural form of equinox should be equinoces. In many other Latin words ending in -x, it is changed to -ces for the plural.173.189.67.3 22:55, 2 October 2010 (UTC)Reelcheeper
 * Why do you think that? What words in Latin do that?  Latin nox: has the plural nominative form noctes, not "noces". --EncycloPetey 23:01, 2 October 2010 (UTC)
 * Never mind what Latin does, this is English isn't it? —CodeCat 23:02, 2 October 2010 (UTC)
 * How about vertex? It goes to vertices in the plural form. —Reelcheeper 07:22, 28 November 2010 (UTC)
 * vertex has a different stem in Latin: vertic-. The stem of nox is noct-. There is a rule in Latin that says -cts becomes -cs (that is, -x). —CodeCat 10:30, 28 November 2010 (UTC)
 * Maybe I should just stick to editing Wikipedia. I'm not very good with English (or Latin). —Reelcheeper 22:37, 28 November 2010 (UTC)
 * Thanks for bringing our attention to the nonstandard plural equinoces. DCDuring TALK 02:29, 27 December 2010 (UTC)

Illumination (of half the earth)
OK, I'm not an astrophysicist, astronomer or even astrologer. But I think this statement is...uninformative: "During an equinox (sense 1), the Sun’s rays illuminate half of the Earth, as shown in this diagram.". (Also, "during" should probably be "at", as it is an instantaneous event.)

True. But I'm pretty sure it is true all year long. Nothing special.

I suspect what is unique is that at the moment the earth crosses the plane of the ecliptic, the night line passes through the poles as shown (though perhaps the axis should be tilted exactly 23.5° toward or away from the viewer). And APPROXIMATELY at equinox, day length=night length. In Seattle, though, that equality will hold on sept 26 (2022), while in Sydney AU, it held on sept 19, 2022. Near the equator, the day length always almost exactly equals the night length. For "almost", see caltech: cso.caltech.edu/outreach/log/NIGHT_DAY/sunrise.htm. (Spoiler: (a) the sun is not a point source and (b) refraction makes it visible even when slightly below the horizon.) Captain Puget (talk) 03:45, 22 September 2022 (UTC)