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Possible new BLP[edit]

Howdy stellar folks, I've been considering an article about Claude Catala, the current director of the Paris Observatory. His citation scores seem high enough (he has been extensively cited) and there should be enough basic information out there for a decent little article. But I thought I'd get some thoughts here before committing. Anyone? Stlwart111 12:43, 18 October 2014 (UTC)

Sounds OK, at least has something about the man. Graeme Bartlett (talk) 10:17, 19 October 2014 (UTC)

Monstrous overmassive black hole in the quasar S5 0014+813[edit]

I was looking upon the List of most massive black holes one morning and found this quasar at the top of the list with an incredible mass of 40 billion solar masses. I came up here because for me that mass is absolutely unbelievably large. How can a black hole be that huge? So I am in doubt if this mass is real or it's just an error. I know you guys have great knowledge regarding this. Is the 40 billion solar mass figure a real thing or just a spoof? Because I really doubt that a black hole can grow that large. SkyFlubbler (talk) 22:47, 29 October 2014 (UTC)

There's a reference :) Unfortunately the formatting is mangled, but the paper it is supposed to point to does derive that figure. Given certain assumptions, etc, etc. ... Lithopsian (talk) 23:02, 29 October 2014 (UTC)
The main issue here is, how can that massive black hole grow? It's much heavier than a dwarf galaxy! SkyFlubbler (talk) 23:37, 29 October 2014 (UTC)
Why is that a problem? The same issue has come up again and again in the history of the study of supermassive black holes, where most of the most massive ones exceed the known methods of growing them, for the time period in which they exist. -- (talk) 06:15, 30 October 2014 (UTC)
Well, I don't see any universal physical mechanism which makes a black hole grow to a 40 billion solar mass pack in just a mere 1.6 billion years after the Big Bang; it's just like the issue of the Her–CrB GW.The thing is, for me the maximum mass of a black hole must be no larger than 31 billion solar masses or something like that. I am not sure of this, but hearing a 40 billion solar mass black hole existing at the dawn of time will definitely put my mind to a pseudo-science thing. So, what mechanism in the universe will make a black hole grow to that monstrous mass in just 1.6 billion years? SkyFlubbler (talk) 07:40, 30 October 2014 (UTC)
First and most important: don't deny the observations. Especially important here at Wikipedia because we are not here to comment, only to report. The peer-reviewed paper says 40 billion so we say 40 billion. Now in this case there is every likelihood that the observation, an extrapolation of a model of what sort of black hole might produce the features that we think would produce that sort of Quasar (aka, a guess!), are exaggerated but that will come out with more research. The other possibility is that further research confirms the huge sizes of these black holes and we have to revise any models that won't allow it. Either way, if and when it happens, we will dutifully describe the results here. So don't get over-excited about every individual paper, but equally don't refuse to include the results on Wikipedia because you personally don't like them. Lithopsian (talk) 13:51, 30 October 2014 (UTC)
Thanks for the comment. I guessed you're right. Science doesn't deal with speculations, only observations. Anyway, I've created the article, and further discussion will be at Wikipedia talk:WikiProject Astronomical objects. SkyFlubbler (talk) 22:16, 30 October 2014 (UTC)

List of largest known galaxies[edit]

I put this list right here because for me this list has many issues:

For me this list is fascinating. One simple reader be extremely fascinated to look for it. However, when I saw it, it was a very poor list, with no references and poor details. For astronomers they will simply laugh at the list since galaxies don't have boundaries. Besides stars a huge dark matter halo is considered to be part of the galaxy. Not to mention that the Milky Way has a million light year dark matter halo. Plus, there are very few galaxies. To be honest I was planning to create the article and I was almost finished with my survey of BCGs of Abell clusters and now found 260 galaxies bigger than one million light years until Asyulus created this article with its current condition, with just 10 galaxies. And I was surprised that IC 1101 is at the top at 6 Mly. To be honest the largest I've found in the 260 I've surveyed is in Camelopardalis and is 15 Mly across. So I think this list must be expanded. More galaxies must be added, with reliable refs. Plus, let's put more precise definitions of the boundary of the galaxy. I need extra help. SkyFlubbler (talk) 03:41, 1 November 2014 (UTC)

The article lists values, these can be checked for in proper references. Those will explain if this is the virial radius or the diameter of luminous material. Have two separate lists on the article, one dealing with the virial radius, the other with the luminous material.
So the "easy" part should be finding references for the current stated values, that will fix the immediate problem of referencing.
The luminous size of galaxies have been used by astronomers to show that dark matter exists, so size is used. The virial radius is also used as a proxy for size
We could have a third list, for galaxy and its system of satellites out to the edge of its Hill sphere... for central galaxy to most distant satellite as the size of the system. (such as how the size of the Solar System is commonly understood, to be the edge of the Kuiper belt, or the last planet)
I would limit each list to the top 100 (yes, arbitrary, but not random, since this is a commonly used cut-off for lists in the world-at-large), to prevent from listing every galaxy known.
-- (talk) 05:16, 1 November 2014 (UTC)
I think the best choice is the Hill sphere of a galaxy as the definition of its boundary. But it doesn't work for very distant galaxies. I can also use the definition of the boundary by the gravitational pull of a galaxy, via computing its mass through the mass to luminosity ratio and determining its gravity. Also, I may also use stellar density, such as the boundary where there is one star per ten parsec squared limit. The virial radius may be unprecise due to the inclination of a galaxy relative to our line of sight.
All those three are good, but let's also include their meanings as to not confuse the reader. Also, even if we limit the list to the top 100 that would still be incredibly huge. I may say only top 30 or 40 to prevent overexagerration.
A little note: I don't know how to search for references. Please help... SkyFlubbler (talk) 08:48, 1 November 2014 (UTC)
You could enter the value and the various galaxy names into or and find a paper/book that supports the value that meets WP:RS -- (talk) 06:08, 7 November 2014 (UTC)
Oh, there should also be another section/list dealing with the angular diameter, as "largest" could mean how large it appears in the sky, and not its actual realspace dimensions. -- (talk) 06:08, 7 November 2014 (UTC)

Pulsational pair-instability supernova[edit]

What to do with this article? Much of it is lifted word for word from the similar Pair-instability supernova article. No references, some fairly bold claims, and very little that I can see that merits a separate article. Fix it? Nix it? Lithopsian (talk) 14:03, 2 November 2014 (UTC)

The Largests List[edit]

Three new lists of astronomical objects are created by an obviously well-intended user. Those are for nebulae, galaxies and planets. However, those lists have no references. Plus, so many wrong info are within it. I don't think that is right for those lists, especially to Wikipedia. I think all of the orders of objects on the list are original research.

But I think it is also my fault, since I created the largests for black holes and cosmic structures, which may "inspired" him. Anyway, I know you guys know this so much. Please add refs to those lists. SkyFlubbler (talk) 22:02, 5 November 2014 (UTC)

Could you link these lists? Sam Walton (talk) 22:07, 5 November 2014 (UTC)
Yes, it'd be helpful to know what lists you are talking about. And you can remind the person creating these lists about WP:V -- (talk) 06:11, 6 November 2014 (UTC)
Oh okay. Here they are:

But I think it would be useless even if I reminded him. I've already messaged him a lot in his talk and he's still unresponsive. I think it must be to the point that he will mention it greatly. SkyFlubbler (talk) 11:33, 6 November 2014 (UTC)w

@Asyulus: -- (talk) 06:11, 7 November 2014 (UTC)
These do seem somewhat problematic, though I wouldn't be against the lists existing. They'd need to be much better than this though. Sam Walton (talk) 12:44, 6 November 2014 (UTC)
^What he said. They're looking better than when they were created, but still need a lot of work. The nebulae one and galaxies one are especially important, although the planet one not so much, because planets are less important in general than nebulae and galaxies. StringTheory11 (t • c) 22:50, 6 November 2014 (UTC)
I think these lists should eliminate the rank column, I don't think that is a supportable column. -- (talk) 06:09, 7 November 2014 (UTC)
Both of you were absolutely right, StringTheory11 and Sam Walton. The thing that makes this list a big deal is because of the fascinating names of titles, of which people will definitely look at it once they've heard it. Putting those poor info, along with no reference points, will spread a frightening hoax in the Internet claiming this and that and linking Wiki as the source. With Wiki being one of the largest websites in the world, it would be a terrible mistake to just leave out the info right there, info that is only an opinion and guesses of an absolutely unknown user, and take it to some presscons etc., and will be finally carved in stone. I don't want again to have another case like the NGC 6872Malin 1 Largest Spiral Galaxy Hoax Case, and a more disastrous Westerlund 1-26 Largest Star Hoax Case that was reported by the ESA. Those two cases are the result of WP:OR in their articles, and now it is so hard to correct the wrong info. So we must fix these lists ASAP.
These three lists are ugly ducklings, with the two being giant ones (the nebulae and galaxies list). This is extremely critical. If we prolong those info for longer it will spread on the Internet like a raging virus and will inform stupid people all over the wotld and will edit the articles on Wiki based on those info. Up until today someone still edit the list of largest known stars with W26 at the top.
To reduce the possible effect of this issue, we must not link it to many articles and fix it. SkyFlubbler (talk) 12:19, 7 November 2014 (UTC)
  • WP:Risk disclaimer -- what is found on Wikipedia is not considered reliable, use at your own risk.
  • WP:NOTFINISHED -- material found on Wikipedia is considered a work-in-progress, and not a completed work. The existence of the lists is not material to what the rest of the internet thinks.
  • WP:Orphan -- information found on Wikipedia should be accessible.
WP:SOAPBOX -- Wikipedia is not a platform to correct the internet.
The galaxy list is not the type of problem you are ascribing to it, since sizing of galaxies is frequently done in amateur astronomy, and has is done in professional astronomy. (such as how to describe hypercompact stellar systems, etc)
The problem is the nebulae list, where if you jumble all the types of nebulae together, the only things that would be listed would be Ly-α Blobs, as they are larger than galaxies. That needs to be converted to a largest nebulae by type table, and separate list tables for largest nebulae by type. I don't think that associations of nebulae should be listed at all, so someone (or when I get around to it, myself) should probably remove those.
I've already deleted the rankings from nebulae and planets, and will do so at galaxies soon. That's the only material that's of serious concern. Slap {{listdev}}s on and they will be shown to be incomplete.
-- (talk) 05:42, 8 November 2014 (UTC)
No, for me all of the lists have problems. On the largest galaxies, as far as you are concerned, I've surveyed the Abell clusters and now found 260 galaxies bigger than 1 Mly. The problem is of all of the 260, only IC 1101 and the Phoenix Cluster BCG are listed. Two galaxies. Two of the 260 multimillion-light-year galaxies. And probably they are not all since I will start my SDSS check. How about the remaining 258? I think it's really not right. Plus, it's obvious that the one who created it is really just an amateur.
For the planets, there are only very few. Of all the thousand planets detected by the Kepler mission, those are only listed? Plus, as far as I'm concerned the largest planet is CT Chamaeleontis b which is not on the list.
The list of nebulae is not a really big problem as you expect; only more or less 50 LαBs are found so far, which is really not a huge number. And 30 of those are interconnected forming the 200 Mly Giant Concentration, making all of the 30 as a single nebula. Problem is we lack references, and those scientists do not give full reports. SkyFlubbler (talk) 04:07, 9 November 2014 (UTC)
Wikipedia is not Citizendium, verified credentials as an authority in the field is not required to write articles.
CT Chamaeleontis b is not a definitively planet, it's likely a brown dwarf.
The state of the lists is that they are under expansion. So, you found 260 galaxies bigger than 1Mly, congrats, now, we can restrict the list to the top 100 entries (plus the Milky Way for comparison) (to the limit of size accuracy, so tied entries get entered to extend past row 100) Many articles are longer than 100 rows, so "100" is not excessively long. As we improve the list, there will be entries that fall off the list. The same applies to planets (keeping Jupiter as a reference entry). An aphorism for you, even the longest journey begins with a single step. The single step was the creation of the articles themselves, now we need to take more steps on the route to better comprehensive coverage, and better accuracy.
The problem with the nebulae list is that it would rapidly become a list of only LαBs, if it isn't divided by type, if that were the case, it really should be called List of Lyman-alpha blobs, but if it should cover other types of nebulae, which it currently does, then we really need to separate them out by type with sublist tables, and have a starting table as a list of largest by type, instead of ending up with a table solely devoted to LABs.
-- (talk) 05:54, 9 November 2014 (UTC)

Need HL Tau article, stat![edit]

Today's NRAO image from ALMA
Jet aimed at HL Tau by HH 151 erm, sorry!
HL Tauri is in the middle of the broad blue area, upper left-center.

Anyone seen this? No, that's not an artist's simulation, that thing is a directly visualized protoplanetary disk!!! But we don't have an article on HL Tau - we have one on HL Tau 76, but I assume this isn't a white dwarf they're talking about! I've never started a star article, so it would be faster if someone here would do that. Also ALMA should be updated to explain the high-resolution mechanism they're calibrating (which I assume is something after the 2013 developments mentioned in the article?). I think this would make a great In The News because it really demonstrates something brand new in astronomy - though I admit, the politics of that process is more than daunting. Wnt (talk) 19:23, 6 November 2014 (UTC)

Different star. The HL in this case is a catalog designation (Haro and Luyten), not a variable start designation, and 76 is the catalog number. Lithopsian (talk) 19:54, 6 November 2014 (UTC)
I can't find a catalogue designation, but I did find an article from 2011 in which scientists looked at HL Tauri (giving at least two references to the star and its position): - so this seems to be a good candidate for an article. Primefac (talk) 20:04, 6 November 2014 (UTC)
I've found an older image on Commons of a jet from HH 151 (second image at right), which the caption says is feeding the formation of stars like HL Tau fed by HL Tau. (erm, oops!) So this is a really pretty story waiting to be told. Wnt (talk) 20:19, 6 November 2014 (UTC)
The reason that we don't have an article on HL Tau is that our coverage of notable astronomy topics is actually pretty shitty, and we're severely undermanned in the topic area, especially with many former regulars now retired or at low activity. Btw, the article should be created at the title HL Tauri, as that is the full variable star designation of the star. My real life schedule's pretty booked at the moment, but it's looking like I'll have some free time next Tuesday to create a stub, if nobody else has by then. StringTheory11 (t • c) 22:47, 6 November 2014 (UTC)
Stub's created. I'll flesh it out this weekend when I'm not about to go to bed. Primefac (talk) 23:37, 6 November 2014 (UTC)
Thanks! I actual edit-conflicted with you on the creation. :) Now I just hope what I added doesn't contain any... doozies. Wnt (talk) 00:25, 7 November 2014 (UTC)
So I'm a bit confused...some news articles say HL Tauri is associated with HH 150 [1], some say HH 151 [2]. Are they both associated with HL Tauri and the articles are just being dumb, or what? Huntster (t @ c) 04:22, 7 November 2014 (UTC)
Sloppy reporting as usual, not least in the NASA press release. HL Tau is HH150. They are coincident within about an arcsecond and are at the same distance. There are three other HH objects within a few arcseconds, HH151-154. HH152 is another variable star, XZ Tau. HH151 a group of fainter knots within the nebulosity, and HH152 even fainter knots. In this image (apparently, since there is no scale or indication of the wavelengths imaged) HL Tau is the star with the bright jet, the bright jet is HH150, XZ Tau is the bright point-like object (although it has its own shells/shocks of nebulosity visible at other wavelengths, HH152), HH151 is the knots towards the bottom of the image, and HH153 is not visible off the top of the frame. Lithopsian (talk) 14:41, 7 November 2014 (UTC)
When all else fails, go for the peer-reviewed journal articles, they (more often than not) give the right answers! Primefac (talk) 19:22, 7 November 2014 (UTC)
Thank you for the clarification Lithopsian, that makes much more sense. So what stellar feature is HH 151 associated with...there's nothing on SIMBAD. Could it be the result of previous outburst activity from HL Tau? (yes, you can call me a dummy if I'm speaking absurdly) Huntster (t @ c) 20:39, 7 November 2014 (UTC)
The caption for the second image talks about orange features where the jet strikes other interstellar material. A third image I've added above has the jet pointed to the left and the orange bits seem more obvious. Wnt (talk) 14:30, 8 November 2014 (UTC)
  • OK, I've put this up for ITN. You can probably think of a better blurb though. Wnt (talk) 23:27, 7 November 2014 (UTC)

New GTRC[edit]

Here's another GTRC. It's on Gliese 876. GamerPro64 22:13, 15 November 2014 (UTC)

WP:OR/WP:FRINGE spammer at Magnetospheric_eternally_collapsing_object[edit]

User:JonathanD has been posting huge textwalls of what looks like original research on Talk:Magnetospheric_eternally_collapsing_object, and adding a lot of OR content, linking MECOs to other topics. A little assistance would be appreciated. - Parejkoj (talk)

This article has suffered from FRINGE before, and was cut down to size before as well. -- (talk) 06:43, 21 November 2014 (UTC)

Proposed merge of two inaccurate lists[edit]

I think the List of largest known galaxies be a section of List of galaxies since it is extremely inaccurate and has no precise definition. For instance radio lobes are part of galaxies since the ejected matter came from the galaxy with some ranging to 16 Mly. Also propose List of largest known nebulae merge to List of nebulae. SkyFlubbler (talk) 00:38, 22 November 2014 (UTC)

Probably a good idea. Defining the largest of these things is always a rather messy thing. - Parejkoj (talk) 04:02, 22 November 2014 (UTC)
I think you should compile that list of 300 galaxies you said you had first. Since really, anything smaller than that list entry saying "300 galaxies" should be removed (except the Milky Way used for comparison). As you point out radio lobes, if a separate list article exists, a separate section of that article can be devoted to sorting by size of radio lobes. (Hence, my prior comments in a section further up this page, on the need to have separate sections split by what criterion is used to determine galaxy size) If we only have a list at the list of galaxies, it should be a table of largest galaxy by type or criterion (ie. largest galaxy by size of radio lobes, largest galaxy by virial radius, naked-eye visual apparent diameter, etc) A subarticle would actually be better for listing galaxies that are not the largest known of each type. Such a table would not actually involve merging anything from the separate list article.
I strongly oppose merging the nebulae into list of nebulae. "List of nebulae" is a list of lists and not an appropriate location to merge that list at this time. We would need to build a new list article in order to merge the largest list. As a compilation list of nebulae does not currently exist, it should not be merged into the list of lists.
-- (talk) 05:54, 22 November 2014 (UTC)

File:CMB Timeline300 no WMAP.jpg[edit]

FYI, there's a discussion at WT:PHYSICS#Featured error? concerning the accuracy of the image and whether it should be nominated for deletion -- (talk) 06:50, 23 November 2014 (UTC)

For clarification, it's less about whether it should be deleted and more about whether it should be a feature image. Primefac (talk) 12:25, 23 November 2014 (UTC)

Questionable deletion of an article in the news[edit]

Now I just don't get how Markarian 177 was nominated for deletion by the fact that it was a big news this week. Here's a link:

This is the first evidence of an SMBH outside a galaxy. It could provide the first evidence of recoil of gravitational waves. And it will be a sight for Hubble next year. So please tell me, why an object in worldwide news is being nominated for deletion? That is very foolish.

I amend to lift the deletion and since I have no more time, I also want for other greater experts to improve the article. SkyFlubbler (talk) 21:11, 23 November 2014 (UTC)

SkyFlubbler, the way it looks to me, an unreferenced, seemingly unremarkable article has been PRODed. This makes perfect sense in my mind. If you think the article can/should be improved, then simply remove the PROD (fortunately it's not an AfD so you can do it yourself). Someone in here might be able to improve it further. Primefac (talk) 21:30, 23 November 2014 (UTC)
Put simply: because the article is rubbish. That object should probably have a Wikipedia article, but it needs to follow the guidelines on content and referencing. If someone writes a decent-quality article, backed up by sources, then we should keep it. But a rubbish article on a notable topic doesn't help the encyclopaedia. Your efforts would be better spent on improving the Markarian 177 article, rather than complaining here. Modest Genius talk 13:34, 24 November 2014 (UTC)