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I get what the local meridian is, but since the celestial meridian is a feature of the celestial sphere, is saying it will pass through the zenith a true statement for any location on Earth? It seems like that would only occur at the equator. (Look at what would happen at the poles.) — Elliot Winkler 05:24, 3 September 2012 (UTC)
This article is confusing and contains at least one error, can someone please fix these problems.
I came to this article to find out what types of meridian there are in astronomy and I am still confused, despite having a good understanding and ability to use right ascension and declination and plenty of experience doing so as an amateur astronomer.
The various definitions of and types "meridian" need to be carefully distinguished, preferably by means of clear diagrams.
I copied this paragraph from the article. It seems to contradict the definition of meridian given. If a celestial object viewed from England, and it crosses the line joining the north celestial pole and the horizon, ie passes "under" the NCP, it will reach it's LOWEST point as it crosses the meridian.
"Because the meridian is fixed to the local horizon, a celestial object will appear to drift past the local meridian as the Earth spins. It reaches its highest point in the sky when crossing the meridian (culmination). Using an object's right ascension and the local sidereal time it is possible to determine the time of its culmination (see hour angle)." — Preceding unsigned comment added by Mark Matthew Dalton (talk • contribs) 02:18, 14 January 2014 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section.A summary of the conclusions reached follows.
The result was no consensus. --BDD (talk) 16:10, 13 February 2015 (UTC)
A recently created stub, central meridian (planet), should be merged into this article, since it seems to deal exclusively with meridians in this astronomical sense ("central meridian" is a special case of astronomical meridian, or is closely related). I would do the merge WP:BOLDly myself but I am not an expert in this topic area, so I'm proposing it here first just to see if an expert will pop by and tell me I've got it all wrong. Ivanvector (talk) 20:31, 6 February 2015 (UTC)
Oppose The two are not the same thing. In planetary astronomy, a central meridian is the planet's longitude which happens to lie at the center of the observable disk. In other words, it is the longitude which is pointed at the Earth. A meridian for an Earth-bound observer is just the plane through the north and south poles, and the north and south point of the horizon. It does not move relative to the observer. Tfr000 (talk) 23:03, 9 February 2015 (UTC)
I'm not sure that I understand the difference, but you've convinced me that you know what you're talking about. If nobody has a different understanding of the two concepts that supports a merge, then this proposal can be removed. Ivanvector (talk) 05:44, 10 February 2015 (UTC)