Wikipedia:Articles for deletion/Earth's circumference

The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.

The result was keep. -- RoySmith (talk) 04:21, 16 December 2018 (UTC)[reply]

Earth's circumference

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Reason: Wikipedia:Content forking. The article has no substantive content that does or could differ from Earth radius. Circumference is merely radius times two pi. Modern literature preferentially uses radius. Strebe (talk) 22:24, 1 December 2018 (UTC)[reply]

I recommend a redirect. The history, measurement, and concept of both circumference and radius are identical. Both are based on an idealized sphere; neither are measured directly; and knowing one implies the other. Strebe (talk) 18:37, 4 December 2018 (UTC)[reply]

I wondered about the same. I disagree because sources treat them separately – circumference is the ancient and practical topic used for navigation and later to define measurements of length (metre, nautical mile), whereas radius is a technical unit used primarily for astronomy. In other words, one is relevant to society, travel and history and the other is relevant to outer space. For the same reason, the two articles cover different content. Onceinawhile (talk) 22:48, 1 December 2018 (UTC)[reply]

And yet, determining the radius and determining the circumference are the same problem. Because the radius is more directly applicable to further calculation (such as area or volume), the topic is preferentially referred to as "radius" in modern literature, including in both geodesy and navigation. I agree that circumference used to be common for the reasons you give, but the Wikipedia way of dealing with something like that is to have "Earth's circumference" (which should be "Earth circumference" in any case) redirect to "Earth radius" with a note in the lede about the one-to-one relationship between circumference and radius. Should we have another article about "Earth diameter" as well, since diameter used to be more commonly used than radius? Surely not. Strebe (talk) 23:02, 1 December 2018 (UTC)[reply]

We should follow the sources. If they cover the topics differently, so should we.

Should all 149 articles in Category:Units of length be merged into one, simply because they are all directly calculable from each other?

Onceinawhile (talk) 00:54, 2 December 2018 (UTC)[reply]

Note: This discussion has been included in the list of Science-related deletion discussions. Bakazaka (talk) 23:16, 1 December 2018 (UTC)[reply]

Should all 149 articles in Category:Units of length be merged into one, simply because they are all directly calculable from each other?. No, because they aren’t. False analogy. Some of those articles are spurious and should be merged. Decimetre, for example, is a stub, will never be anything but a stub; and concerns a thing that has no history or development independent of the meter and that is defined as a calculation from the meter. Foot (unit), on the other hand, is not defined by the meter or any other unit, has many variants, and has a history independent of other units. The fact that someone or even a standards body has given equivalences does not thereby mean they are defined in terms of each other. While an inch is always 1/12th of a foot, its history and origin is independent of the foot, so it’s a reasonable candidate for a separate article. For a more reasonable treatment of topics, see Trigonometric functions, where the basic trigonometric units are all presented in one article because they all derive from the same basics. That is instead of separate articles for sine, cosine, tangent, etc. Meanwhile, circumference and radius are invertible, and now you have gobs of material that duplicates what’s already in Earth radius.

The “follow the sources” argument also does not hold, and for the same reasons. We do not have a separate article on quadrature as distinct from numerical integration even though the early literature preferentially uses that term. Strebe (talk) 02:00, 2 December 2018 (UTC)[reply]

~~Keep~~ There are different precedents for separating or combining topics that can be derived from each other, as in most of the measurement unit articles, and decision on a case-by-case basis seems to be the usual (sensible) approach. In this case, I think there is a distinct difference in article focus - Earth radius deals with measurement methods and the physical side; Earth's circumference is almost entirely historical in content. I suppose a workable merge could be engineered, but I don't really see the necessity. In any case, it's not content duplication/forking. --Elmidae (talk · contribs) 11:00, 2 December 2018 (UTC)[reply]

This article duplicates large swaths of the article, where the historical circumference measurements are discussed in detail. As for a “merge”, this article is brand new.

That's actually correct - the expanded material would fit better in there. Change to merge to History of geodesy. (I don't see what the new status of the article has to do with anything, though; much of the material seems not to be covered in the latter). --Elmidae (talk · contribs) 20:15, 2 December 2018 (UTC)[reply]

@Elmidae: what about the other sections? The article is still being built, but there are already at least two other sections which would not fit into History of Geodesy. Onceinawhile (talk) 20:44, 2 December 2018 (UTC)[reply]

Keep Seems to me Earth’s circumference would have to deal with the seashore problem, where the more closely something is examined the more fractal iterations interfere with averages. Somebody must have written something about this. Hyperbolick (talk) 14:59, 2 December 2018 (UTC)[reply]

Circumference, and specifically this article, concerns only the circular model. Strebe (talk) 19:23, 2 December 2018 (UTC)[reply]

Redirect: while the article does or should entirely duplicate the content of existing articles (Earth radius, History of geodesy, etc.), there is nothing inherently wrong with the title. I suggest a redirect to Earth radius, but divining a reader's intent might offer a different target. Anything not already present but considered useful should be merged to the relevant title. Lithopsian (talk) 19:36, 2 December 2018 (UTC)[reply]
merge or redirect as the topics are seriously overlapped. Although circumference seems to be a more correct term, as that is what is measured, and the radius has not been directly measured, and will take a while before it is. (Perhaps diameter can be measured using gravitational waves, or a neutrino burst, but that is yet in the future when more sensors exist). Graeme Bartlett (talk) 22:31, 2 December 2018 (UTC)[reply]

Although circumference seems to be a more correct term, as that is what is measured, It is not. What is measured are angles consisting of straight lines, which, through the presumption of a spherical earth, yields an imaginary arc of a circle via trigonometry. Again, with the presumption of a spherical earth, this arc is extrapolated into a circumference and radius. Strebe (talk) 23:54, 2 December 2018 (UTC)[reply]

Keep: so far we have consensus that this is a legitimate topic, but a variety of other articles have been pointed out where there is topic overlap. We can also add history of the metre, nautical mile, circle of latitude, meridian (geography), as well as Earth and Equator (notably, the latter two being the prior targets of the two primary redirects [1], [2]).

Lithopsian posed what I think is the key question here – what would an average reader, searching for “Earth’s circumference”, or similar, expect and want to find? If it is just “how long is it”, they don't need to click on Wikipedia. I think they mostly come here to find out “what is measurement of the circumference used for” or “why is the Earth’s circumference important”? This article now does that, and could do even more if it was given time to develop. Before this article, this information was dispersed across perhaps a dozen articles, making the journey to understanding laborious and complicated.

Some merge proposals have suggested Earth radius – this is a highly technical article, aimed at geodesists, which answers different questions and is focused on the defined astronomical unit R_🜨. Another suggestion is history of geodesy, since part of that article’s scope overlaps with part of this article’s scope – in the way that human height partially overlaps with history of anthropometry.

There is no good single target article for a merge, and having this information dispersed back across a dozen articles would not help the reader. Hence the status quo serves the reader best. A compromise might be a “merge and demerge” with Earth radius to create a concept article called Earth radius and circumference (or something similarly inclusive) and a separate article called Earth radius (unit).

Onceinawhile (talk) 07:49, 3 December 2018 (UTC)[reply]

Some merge proposals have suggested Earth radius – this is a highly technical article, aimed at geodesists, which answers different questions and is focused on the defined astronomical unit R_🜨. Not so. Nothing beyond the symbol has anything to do with the astronomical R_🜨, and rather little of it has to do with anything geodesists concern themselves with, either. Geodesists are interested in the ellipsoid and geoid, not sphere, and therefore do not concern themselves with "radius" except as a digression. The article's bent is, actually, about an idealized radius for an idealized sphere, which is the same concern, history, measurement, and mathematical foundation for a circumference. If the article needs to be reformed or enhanced to better serve readers who might not realize circumference and radius are inseparable, then that is a project I could get behind. The fact that they are inseparable, however, argues against two articles for the same topic. Strebe (talk) 17:25, 3 December 2018 (UTC)[reply]

Relisted to generate a more thorough discussion and clearer consensus.
Please add new comments below this notice. Thanks, North America¹⁰⁰⁰ 02:36, 8 December 2018 (UTC)[reply]

Comment this is obviously a reasonable search term; Figure of the Earth would probably be a better target than Earth radius currently. As Earth is not a perfect sphere, this isn't simply a mathematical function of Earth's radius. power~enwiki (π, ν) 04:07, 10 December 2018 (UTC)[reply]

As Earth is not a perfect sphere, this isn't simply a mathematical function of Earth's radius. It is. Because earth is not a perfect sphere, radius also has no precise meaning, and in exactly the same way as circumference cannot. (This is noted in the Earth radius article.) Strebe (talk) 07:49, 10 December 2018 (UTC)[reply]

Keep In a purely mathematical sense, circumference is a function of the radius. However, in a more practical sense, the two have been used differently. Sailors did not navigate using the Earth's radius. Technically, they could have, the reality is, they didn't. As such, two separate articles are needed to reflect the difference in practical usage of the two concepts. This holds true, even if much of this article is repeating information that is already written in Earth radius. - Puzzledvegetable (talk) 21:01, 10 December 2018 (UTC)[reply]
Keep. Per the reasons cited by others here, especially those of User:Puzzledvegetable, and also because I am not convinced by the argument about modern literature favoring radius over circumference. That's especially not the case for the literature I am used to reading: historical studies and the history of science, especially every single time the name Eratosthenes and his achievements are mentioned. If someone wants it, I could probably even produce an exhaustive list of scholarly sources that use the term almost exclusively over radius, if you want to play the WP:SOURCES and WP:RELIABLE game here. Pericles of Athens^Talk 06:17, 14 December 2018 (UTC)[reply]

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.