Talk:List of periodic comets
|WikiProject Solar System||(Rated List-class, Low-importance)|
|WikiProject Astronomy / Astronomical objects||(Rated List-class, Low-importance)|
List of periodic comets
Why is the comet Hale-Bopp not on either list? Not the numbered list, or the unnumbered list. KellyCoinGuy
Add Next perihelion
It would make sense to be able to sort this table according to next perihelion. The data is already there (most of the comets have it in their little info-box) but transfering it by hand would be a PITA. Is it possible to do it with a bot or something? I don't have the Wiki-fu to pull it of, but if anyone does, please do it! =) 126.96.36.199 (talk) 02:17, 20 November 2009 (UTC)
- I am against it. It would be better to sort list of unnumbered periodic comets by designation. — Chesnok (talk • contribs) 03:29, 20 November 2009 (UTC)
- I came here specifically to find a list of comets by date. In fact, what I really wanted was a historical list by date of discovery. I would have thought that a sortable list which included this as well as next perihelion would be perfectly justified. --Coconino (talk) 07:54, 14 October 2010 (UTC)
I agree that this list needs more columns to be useful. I was hoping to easily find which comets have the largest orbits or the longest periods. Just names and numbers aren't really all that useful. --Lasunncty (talk) 21:26, 7 July 2012 (UTC)
Why the Comet C/1861 J1 is include in the List of unnumbered periodic comets?. I mean The Comet C/1861 J1 have a revolution period of a least 400 years and only one perihelion passage and a periodic comet is defined to have a revolution period of less than 200 years or confirmed observations at more than one perihelion passage —The preceding unsigned comment was added by 188.8.131.52 (talk • contribs) 06:20, 6 June 2007 (UTC).
- It have been observed during two perihelion passages. Comet C/1861 J1 = Comet C/1500 H1. (This was proved by I. Hasegawa and S. Nakano , but the comet did not recieve an official number.) --Chesnok 11:01, 6 June 2007 (UTC)
Non-numbered periodic comets
This list should be renamed to either List of numbered comets or List of numbered periodic comets, or alternatively non-numbered periodic comets should be included this list. Now the title/content is somewhat misleading as the majority of periodic comets is missing.--Jyril 22:48, 21 December 2005 (UTC)
- Can you provide an example for a missing comet? This list is taken from the official page at the IAU (See "External links"). AFAIK, there are no other officially recognised periodic comets. Awolf002 22:58, 21 December 2005 (UTC)
- I agree that there seems to be some ambiguity in the definition of periodic. Here is a part of the IAU resolution text :
- 3. The nature of an object can further be indicated by an initial prefix. In particular, such prefixes should be applied in cases where comets have possibly been misdesignated as minor planets, or vice versa. If necessary, the prefix A/ would precede a comet designation that actually refers to a minor planet (or asteroid). For comets the acceptable prefixes are P/ for a periodic comet (defined to have a revolution period of less than 200 years or confirmed observations at more than one perihelion passage) and C/ for a comet that is not periodic (in this sense), with the addition of X/ for a comet for which a meaningful orbit can not be computed and D/ for a periodic comet that no longer exists or is deemed to have disappeared.
- 4. If a comet is observed to return (or have its periodicity established by observation through aphelion or from identifications), the P/ (or D/) shall be preceded by an official sequential number (e.g., 1P/1682 Q1 = Halley), the list to be maintained by the Minor Planet Center and published in the Minor Planet Circulars. Subsequent recoveries shall be acknowledged with further designations only when the predictions are particularly uncertain.
- I read this as: Use P if the orbit is found to be elliptic with a period of less than 200 years, but only put it into the number periodic list if confirmed by second perihelion, or identifications of previous apparitions, or if the observations span the current aphelion. So, this article represents the numbered periodic comet list, I guess. Comments? Awolf002 19:26, 22 December 2005 (UTC)
I see that the unnumbered periodic comets are now part of this page. That may be fine (as discussed above), however I feel nervous about all those red-links set for all those comets. I do not believe that each and everyone of them is notable enough to warrant an article! Can we agree to remove the red-links, and only add article links, when there is something to write about and an article exists? Awolf002 12:36, 1 February 2007 (UTC)
Proposal to rename page
I've made a few comments on various comet-related pages about this issue. IMO defining "periodic comets" as comets with a period of less than 200 years is extremely confusing. Comets with periods of > 200 years are just as "periodic". I understand that some authorities use this terminology, but others seem to use the more sensible term "short-period comets". I think in Wikipedia we should lead with the term "short-period comets", and mention parenthetically that some use the term "periodic comet" instead. To this end I suggest that this article is renamed "List of short-period comets". Any objections? Matt 22:02, 25 December 2007 (UTC).
- Object: As you correctly write, a periodic comet is only called periodic when the period is lower than 200 years, as defined by official agency assigning the title periodic (prefix P). This list represents those comets and as such should be called in way that does not conflict with that definition. (If you want to quibble with the reasoning why these are called periodic, that would be another type of discussion.) Just my 2 cents. Awolf002 (talk) 00:56, 26 December 2007 (UTC)
- Hi again. No, I don't want to quibble with any official definitions. If the astronomical community calls them "periodic comets" rather than "short-period comets" then we should clearly use that term. But per my comment at Talk:Comet#Confusion/contradiction I think that if we must stick with calling them "periodic comets" then an explanatory note for the non-specialist is necessary to allay the reader's fears that a mistake has been made. I first looked at these two articles -- List of periodic comets and List of non-periodic comets -- ages ago, and just assumed that there was just some Wikipedia-specific muddle and confusion about terminology, or the article started out as one thing and then morphed into another, or something like that. It's only recently that I've spent a bit of time looking into it that I've finally figured out what's going on. Matt 03:17, 27 December 2007 (UTC). —Preceding unsigned comment added by 184.108.40.206 (talk)
I'm most interested in how (and when) the various periodic comets were discovered. I know that Halley's Comet appeared many times since antiquity, but how come no one realized it was the some object till the eighteenth century?
- From probably 18th century till now numerous astronomers were systematically observing night skies for finding these small fuzzy objects. Conviction that comets are atmospheric phenomena was common for many centuries. When it came out that they are celestial objects, some people began hunting for it: first visually, since 1892 - visually and photographically, and since 1980s - with CCDs. Now visual comet hunting is very inefficient because there are many large sky surveys that scan the sky and identify objects automatically. But amateur astronomer still can discover a comet with CCD. — Chesnok (talk) 20:17, 24 February 2009 (UTC)
Do we have agreement that each comet should eventually have an article, and do we also have agreement that each person who discovers a periodic comet should have an article? Is this notable enough? I would like to create some stubs for discoverers, with this fact as the anchor to their notability, but i dont want to deal with AFD's if possible. Do we have policy on this?Mercurywoodrose (talk) 23:56, 16 September 2010 (UTC)
last/next perihelion out of date
About 40 of the dates in the next perihelion column are in the past. Recently passed dates are one thing, but most of these are years in the past. The worst offender passed more than a decade ago. Jelloman (talk) 02:52, 16 July 2015 (UTC)