Talk:Sagitta

Orion reference

I changed the reference to Orion as violating the Bayer rule of naming the stars in order of brightness into Sagittarius as Orion actually conforms rather well with Beta only being slightly brighter than Alpha and Alpha being variable and possibly brighter when Bayer named them. Sagittarius however has its two brightest stars named Epsilon and Sigma with Alpha way down in the list.--Kalsermar 17:52, 7 November 2005 (UTC)

Depth of curve of a telescope mirror.

Defined by the formula

$S={\frac {r^{2}}{2\times ROC}}$

or

$S={\frac {r^{2}}{4\times focallength}}$

it refers to the glass removed to yield the optical curve. I am writing a book over at Wikibooks on Telescope making and would love to link to an article here at Wikipedia that referenced this bit of knowledge.

vorblesnak@peak.org —The preceding unsigned comment was added by 69.59.203.142 (talk) 20:40, 17 March 2007 (UTC).

Sagitta (optics)? ... said: Rursus (^mbork³) 15:23, 3 November 2009 (UTC)

Geometry

There needs to be a reference to the geometric term "sagitta" - which does not just refer to telescopic mirrors, but more broadly, to the depth of any arc. It is used extensively in architecture when calculating the arc necessary to span a certain height and distance.

Defined by the following, where s equals sagitta (the depth of the arc), r equals the radius of the circle, and l is one half the distance across the base of the arc:

$s=r-{\sqrt {r^{2}-l^{2}}}$

or

$r={\frac {s^{2}+l^{2}}{2s}}$

Architects, engineers, and contractors use these equations to create "flattened" arcs that are used in curved walls, arched ceilings, bridges, and numerous other applications.

I'll try to find it. Versine is also called "sagitta", but that's a third thing. ... said: Rursus (^mbork³) 15:13, 3 November 2009 (UTC)

Didn't find it. Made it! Sagitta (geometry)? ... said: Rursus (^mbork³) 15:27, 3 November 2009 (UTC)

This article name

If my creation of Sagitta (geometry) and Sagitta (optics) were correct, we should consider moving this article to Sagitta (constellation) and let this article name contain a disambiguation. ... said: Rursus (^mbork³) 15:37, 3 November 2009 (UTC)

@Rursus: (only ten years later..hahaha) but seriously, I think the constellation is far more notable than the other two....Cas Liber (talk · contribs) 19:44, 3 February 2020 (UTC)

Did I really create the articles of Sagitta (geometry) and Sagitta (optics)? That must have been an earlier incarnation of me. I rather suspect that I copied someone else's talk comments, and that he/she/they are the real creators. As for notability, the only way to measure that is perhaps using any neutral search engine and see what one gets in what order. Rursus dixit. (^mbork³!) 14:02, 4 February 2020 (UTC)

Sagitta in geometry and sagitta in optics are of course the same thing ;) Lithopsian (talk) 18:10, 4 February 2020 (UTC)

I agree. This situation seems very similar to Cygnus, Gemini, Draco, Virgo, Pisces, Aquarius, Libra, Aries, etc. Arguably also Lyra (disambiguation) should be moved to Lyra, Cetus (disambiguation) -> Cetus, and so on. constellation is far more notable – my impression is that this constellation is not all that well known or commonly discussed, except by astronomers and astrologers. I would guess at least as many people have heard of the geometry term. But I haven't done any detailed survey. YMMV. –jacobolus (t) 02:41, 1 December 2022 (UTC)

For what it’s worth, a Google scholar search seems to return mostly references to sagitta (arrowworm), to one kind of otolith (structure in the inner ear of certain fishes), to a species of lumpenus (fish), and to a species of ligularia (plant), along with a handful of geometry-related results. I don't see any references to the constellation among the first several pages of results. –jacobolus (t) 02:54, 1 December 2022 (UTC)

Myths

Moving here some of the myth stuff, that couldn't find their citations (yet):

--§1--

Sagitta was further interpreted by some as Cupid's Arrow or as an arrow shot by Sagittarius at Scorpius.

Other interpretations consider the arrow to have been shot by Centaurus at Aquila, since Centaurus faces the correct direction and is at an appropriate angle to the arrow, whereas Sagittarius is immediately below it facing in the opposing direction (i.e. towards Centaurus).

As a result of the interpretations where Centaurus shot the arrow, may have come the myth in which Chiron (who was usually identified as Centaurus), having been painfully wounded by Herakles, gives up his immortality to rid himself of the pain, and takes the place of Prometheus, Herakles/Chiron then killing Aquila so that Chiron doesn't suffer as Prometheus did. As such, together with Lupus, this may have formed the basis of the tale of the Erymanthian Boar (which was one of Herakles' labours).

The sentence "Others believe the Arrow to be the one shot by Hercules towards the adjacent Stymphalian birds (6th labor) who had claws, beaks and wings of iron, and who lived on human flesh in the marshes of Arcadia - Aquila the Eagle and Cygnus the Swan, and the Vulture - and still lying between them, whence the title Herculea." appears to have derived from R.H. Allen's "Star Names: Their Lore and Meaning" (1899), which it paraphrases closely. However, Allen gives no attribution to this claim, stating merely: "(Sagitta)...has been regarded as the traditional weapon...shot by Hercules toward the adjacent Stymphalian birds..." — Preceding unsigned comment added by Idaho Astro (talk • contribs) 21:39, 28 January 2016 (UTC)

... said: Rursus (^mbork³) 16:18, 3 November 2009 (UTC)

Star tales (a reliable source) tell us a story where Sagitta is sent from Eros (Cupid) towards Ganymede (representend by Aquarius) on instigation on Zeus. Star tales refers to Germanicus Caesar. ... said: Rursus (^mbork³) 16:47, 3 November 2009 (UTC)

File:Sidney Hall - Urania's Mirror - Delphinus, Sagitta, Aquila, and Antinous.jpg to appear as POTD soon

Hello! This is a note to let the editors of this article know that File:Sidney Hall - Urania's Mirror - Delphinus, Sagitta, Aquila, and Antinous.jpg will be appearing as picture of the day on February 4, 2016. You can view and edit the POTD blurb at Template:POTD/2016-02-04. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page. — Chris Woodrich (talk) 23:57, 15 January 2016 (UTC)

Picture of the day

A plate from Urania's Mirror depicting the constellations Delphinus (the dolphin), Sagitta (the arrow), and Aquila (the eagle), as well as the former constellation Antinous (according to legend, a young man who saved Hadrian from drowning).Illustration: Sidney Hall; restoration: Adam Cuerden

Theta is three stars?

The text describes how Theta Sge was originally seen as a single star but now known to be three that are called HR 7705? This is a rather strange statement, especially in the lead of the stars section. Several of the constellation's main stars are multiple and I'm not sure what is special about Theta. It is a borderline naked-eye star with two companions well below naked-eye visibility. There is nothing there that adds or detracts from the fact that it was and is called Theta Sge. HR 7705 is one of the three and the other two have separate designations. Should the sentence be dropped? Is it trying to make some point that I have missed? If it is making some special point, does it need a citation? Lithopsian (talk) 14:06, 31 January 2020 (UTC)

@Lithopsian: Feel free to tweak it as needed. This constellation has a bunch of highly unusual stars and I keep getting sidetracked...I think I started adding one-liners as place-holders many moons ago. Cas Liber (talk · contribs) 19:41, 3 February 2020 (UTC)

Exoplanets

The lead (and the starbox) states that two stars in Sagitta have planets. The body only mentions one. Given what the lead says, two should be mentioned. Are there really only two? Small constellation, but there are thousands of known exoplanets now. Not sure how to check definitively and obviously subject to change. Lithopsian (talk) 14:11, 31 January 2020 (UTC)

Found the other and added. Yes might be worth dropping te "two"...Cas Liber (talk · contribs) 19:43, 3 February 2020 (UTC)

Bookmark

See [1] - yay another RCB star :) Cas Liber (talk · contribs) 19:43, 3 February 2020 (UTC)

Scary block of text

I just came to have a little look at the article and see if anything struck me that could be improved. Sagitta#Stars jumped out as unreadable due to a combination of a lot of numbers, symbols, and inline references. It is also quite a large section without any quick-reference points, so you're faced with just reading it from start to finish to see what's going on. One possibility is to reduce the number of inline references for fairly factual features about stars that have their own articles. I know this article should stand alone and be verifiable, but its just an idea. I don't know how much less scary it would actually make things. The other thought is the margins of error on (nearly) everything. The differing plus and minus ranges in particular cause line spacing issues and are not the sort of things that encourage the average reader. Some constellation articles (eg. Orion (constellation)) use a list-type layout to break up the equivalent section. Not sure it would work here with the number and types of stars we described, but it seems to work well in the right place. Lithopsian (talk) 20:24, 30 August 2020 (UTC)