Talk:Detached object

Detached object has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.

Article milestones
Date	Process	Result
July 26, 2008	Good article nominee	Not listed
November 12, 2009	Good article nominee	Listed

A fact from this article appeared on Wikipedia's Main Page in the "Did you know?" column on July 17, 2008.

The text of the entry was: Did you know ... that there are nine known trans-Neptunian detached objects in our Solar System?

Current status: Good article

No sections?

Before this gets GA reviewed, is there really not enough content to warrant sections? Gary King (talk) 07:44, 15 July 2008 (UTC)[reply]

I dunno, I mean... is there a "must have sections" requirement on WP:WIAGA? Ling.Nut ^(WP:3IAR) 08:11, 15 July 2008 (UTC)[reply]

Added some. Serendi ^pod ous 08:12, 15 July 2008 (UTC)[reply]

Buie

Looking these guys up on Buie it seems that (82075) 2000 YW134 might be in a 8:3 resonance. But the last observation shows as 2004/04/16. The Lykawka reference in this article was written in 2006. Lykawka looks to have used a 4–5 Gyr integration while Buie is only doing a 10My integration. So I am not sure what to think of this yet.

Another article [1] lists as 8:3 resonant. Other detached objects are also listed as high order resonant is this article. Ruslik (talk) 07:34, 18 July 2008 (UTC)[reply]

Buie shows 2003 UY291 as classical. But again the last observation was 2005/12/02. I am not sure how to explain this unless Lykawka used an older data set for his calculations. -- Kheider (talk) 06:24, 18 July 2008 (UTC)[reply]

new farthest member: 2006 SQ372?

read here: [2]. Nergaal (talk) 19:39, 29 September 2008 (UTC)[reply]

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WGF-4MY0MMW-3&_user=501045&_coverDate=07%2F31%2F2007&_rdoc=1&_fmt=full&_orig=search&_cdi=6821&_sort=d&_docanchor=&view=c&_acct=C000022659&_version=1&_urlVersion=0&_userid=501045&md5=2b3500fe6862a3e74724d7647fb8070d#tblfn008

Looking at the MPC's List Of Centaurs and Scattered-Disk Objects: 2006 SQ372 has a perihelion @24AU and is under the influence of both Neptune and Uranus, so I don't think we should call it detached. When Uranus and Neptune were migrating outward, 2006 SQ372 must have had a very close fly-by of one of them.
2007 TG422 also comes within some influence of Neptune, but I do wonder how 2007 TG422 achieved a perihelion of 35AU with an aphelion of 900+AU. Perhaps Neptune migrated outwards to 35AU and then back inwards to 30AU. During Neptune's migration there would have been a period were Neptune had a higher eccentricity. -- Kheider (talk) 07:58, 21 January 2009 (UTC)[reply]

Hills cloud merger

My initial thought is that it may be premature to combine the two. The spherical Hills Cloud is still somewhat hypothetical in that it can not yet be shown to exist. But computer simulations show that known objects are "detached" (beyond significant gravitational interactions with Neptune's current orbit.) Only 3 of the current detached candidates have aphelion well beyond 100 AU. -- Kheider (talk) 22:01, 26 January 2009 (UTC)[reply]

OK. I'll take the merge notice down. Serendi ^pod ous 22:02, 26 January 2009 (UTC)[reply]

Trim down table?

Emel’yanenko and Kiseleva (2008) (subscription required)

Nergaal (talk) 01:45, 28 January 2009 (UTC)[reply]

Actually that article makes the list bigger. :-) Most of the 100% resonance probability objects are simple 5:2 resonances. Some notable likely resonances are:

(131696) 2001 XT254 7:3 (100%)
(119878) 2002 CY224 12:5 (84%)
(136120) 2003 LG7 3:1 (79%)

-- Kheider (talk) 08:56, 28 January 2009 (UTC)[reply]

C-class

In April of 2009, Marc Buie informed me that that they (the Deep Ecliptic Survey?) were "in the process of revising our classification scheme (hopefully for the better)." I have since looked at some of the objects that I have used Buie to list as ScatEXT (detached) and most are now listed as ScatNEAR. I then realized that I no longer had any idea how to properly perceive a true ScatEXT object. We need to find out how the DES or minor planet is now defining ScatNEAR/EXT objects. I honestly don't think they are using their old 2005-2006 definition. Thus, I have also lowered this article to C-class. -- Kheider (talk) 17:34, 15 August 2009 (UTC)[reply]

The DES is working on their software. Some of their links are not even currently active. I think this article might need more "peer reviewed" papers to qualify for GA level. In August I was bold and actually lowered this article from B-class to C-class. But perhaps others think it is GA level. -- Kheider (talk) 21:40, 16 September 2009 (UTC)[reply]

I don't necessarily agree... link rot's a perennial problem, but I'm prepared to accept that those references existed when they were added, and I don't think any of them are citations for controversial facts.

I do think it's a potential GA given a bit more citing the obvious, but I'll defer to your view and add a requirement for working citations to the GA review.—S Marshall ^Talk/_Cont 21:52, 16 September 2009 (UTC)[reply]

I am waiting for further clarification, but even 20000 Varuna is currently showing up as Scat-Ext using the DES. Varuna has a perihelion of 40 AU and an aphelion of 45AU, but I think it is the modest inclination of 17 degrees that stirs the pot. Yet the MPC lists Varuna as a Cubewano. (Yes, the DES use to list Varuna as Classical.) I am fearful that the exact definition of a detached object is a moving target at this time. -- Kheider (talk) 22:16, 16 September 2009 (UTC)[reply]

Well, in GA review terms, I've asked for a clear definition of what a Detached Object is to appear in the lead. Let's see what appears? :)—S Marshall ^Talk/_Cont 23:23, 16 September 2009 (UTC)[reply]

In regards to the GA review: (1) Marc did some further updates at the end of August to the software (still may be on-going for a few weeks) and (2) Obviously, some objects are very clearly detached. -- Kheider (talk) 23:53, 16 September 2009 (UTC)[reply]

The Deep Ecliptic Survey references (Orbit Fit and Astrometric record) seem to up and running again and are no longer strongly in conflict with previous results. But:

(48639) 1995 TL8 is coming up classical.
2006 QH181 has a good chance of being in resonance with Neptune.
(82075) 2000 YW134 has being coming up as 8:3 resonance using DES for quite some time.
2003 UY291 is coming up classical.

Keep in mind that if I was to take the DES results as flawless I would have to accept a lot of objects as detached that are also classical, ie.: 20000 Varuna and Makemake. But then again, perhaps it is correct to say that all un-perturbed objects are detached. Where do we draw the line since the Minor Planet Center and Deep Ecliptic Survey define classical somewhat differently? The DES runs a 10 million year simulation, I do not know how exactly the MPC defines a classical object. -- Kheider (talk) 22:01, 4 October 2009 (UTC)[reply]

Update?

The last detached object in the list was discovered in 2006. Have there been any new detached objects discoveries since that time? --Jan.Kamenicek (talk) 12:38, 11 February 2012 (UTC)[reply]

Yes, probably. 2012 DR30, f.ex. is somewhat interesting:

It seems it has a large a ~1100 AU, as can be seen in the list:

http://www.minorplanetcenter.net/iau/lists/Centaurs.html

There are a few other candidates too, such as 2010 BK118 and 2007 TG422, but the trouble is that someone have to call them "detached objects" before the Wikipedia editors – we cannot just assume "they are detached objects" because of any criterion. Rursus dixit. (^mbork³!) 17:22, 14 November 2012 (UTC)[reply]

2012 DR30 and 2010 BK118 are nowhere possibly detached objects, they have perihelia within the orbit of Uranus (resp. 14.5 AU and 6.1 AU)! 2007 TG422 has a perihelion distance of a pretty typical scattered-disc object (q=35.6 AU) [3]. However, any object with q comfortably above 40 AU is very likely to be detached. The list of the Minor Planet Center gives two more 'recent' ones, 2009 KX36 (q=44.7 AU, a=90.9 AU) and 2008 ST291 (q=42.6 AU, a=157 AU), but no objects with q>40 AU more recently discovered than those. --JorisvS (talk) 20:02, 14 November 2012 (UTC)[reply]

Since the DES/Buie 10 million year simulation was used as a source in this article and moved to a new server in 2009 with different software libraries (gremlins), I have often wondered if the 2009 version of this list was better. -- Kheider (talk) 14:40, 9 February 2016 (UTC)[reply]

average distance

Can someone expand the table to add the semimajor axis length to the table? -- 70.24.250.235 (talk) 09:00, 29 March 2014 (UTC)[reply]

Done; semi-major axis added. --JorisvS (talk) 11:58, 29 March 2014 (UTC)[reply]