Wikipedia:Articles for deletion/List of largest nebulae


 * 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. While there was some agreement on moving the article, there isn't enough consensus here to make that happen. A move discussion can take place on the article's talk page if desired.  —&#8288;Scotty Wong &#8288;— 05:42, 29 July 2021 (UTC)

List of largest nebulae

 * – ( View AfD View log )

Deprodded in January 2021 by without explanation or improvement, 2 hours before it was eligible for deletion. The PRODder,, was concerned that this list is woefully incomplete to the point of being inaccurate, is based entirely on WP:SYNTH, mixes different size metrics for non-compact objects, and fails WP:LISTN. There are also concerns that it inappropriately lumps together Lyman-alpha blobs and high-velocity clouds with other types that are much smaller. See also Articles for deletion/List of largest galaxies, a similar AfD from 2018. –LaundryPizza03 ( d c̄ ) 18:30, 21 July 2021 (UTC)
 * Note: This discussion has been included in the list of Astronomy-related deletion discussions. –LaundryPizza03 ( d  c̄ ) 18:30, 21 July 2021 (UTC)
 * Note: This discussion has been included in the list of Lists-related deletion discussions. –<b style="color:#77b">Laundry</b><b style="color:#fb0">Pizza</b><b style="color:#b00">03</b> ( d  c̄ ) 18:30, 21 July 2021 (UTC)


 * Keep The largest astronomical objects naturally attract attention on account of their size, whether its absolute or apparent. So, notice that we have lots of similar lists like the List of largest cosmic structures, List of largest stars, List of most massive black holes and many other Lists of superlatives in astronomy.  Nebulae such as the Tarantula Nebula are naturally included in this as they are major astronomical objects.  The only complication is that there are different kinds of them and so we don't have a single list of nebulae, rather we have several lists of nebulae.  The nomination mentions another AfD for the List of largest galaxies.  Notice that this did not result in deletion but that the title was redirected to the list of galaxies where similar content is found.  That solution won't work in this case and so some more considered approach is needed.  The nomination complains at the lack of the improvement but notice that neither the nominator nor the prodder have made any constructive improvement.  See WP:POT and WP:SAUCE.  See also WP:DINC.  Andrew🐉(talk) 20:17, 21 July 2021 (UTC)
 * Keep Being complete is never a requirement for a list to exist. This aids in navigation and gives far more information than a category would.  Use the talk page to discuss any changes that need to be done.   D r e a m Focus  21:32, 21 July 2021 (UTC)
 * Comment The WP:LEAD currently reads Below is a list of the largest nebulae so far discovered, ordered by size. This list is prone to change because of inconsistencies between studies, their great distances from our stellar neighbourhood, and constant development of technology and engineering. Nebulae's boundaries are also undefined, and is also prone to change. Lastly, scientists are still defining the parameters and defining features of nebulae. Because of all these scientific inconsistencies, this list might be unreliable. That seems to bear out the concerns noted in the nomination. Superlative lists are usually fine, but we need to be able to tell what qualifies to be on the list and how to order the entries. In other words, we need proper WP:LISTCRITERIA and at least a fairly well-defined measure which is applied consistently by WP:Reliable sources. Do we have that here? TompaDompa (talk) 23:03, 21 July 2021 (UTC)
 * Move to List of nebulae. The size criterion is inherently unreliable, and not even followed by the list itself. Makes more sense to simply rename it as a list of nebulae, as this is what it is. This also solves the lack of criterion: like list of galaxies, it is explicitly fuzzy. Tercer (talk) 10:20, 22 July 2021 (UTC)
 * As I explained above, List of nebulae already exists as a redirect and the page that it redirects to is a list of lists, not a single page like the list of galaxies. So, it's not the same structure. Andrew🐉(talk) 10:43, 22 July 2021 (UTC)
 * I'm aware of that. I'm suggesting removing the current Lists of nebulae. The content there is trivial, it's no loss getting rid of it. Tercer (talk) 11:50, 22 July 2021 (UTC)


 * Move to List of nebulae; I would rather have it in there. The thing here is, our data regarding the size of nebulae is still too inconsistent to make an appropriate list. Nebulae can range anywhere from small Bok globules to galaxy-sized Lyman-alpha blobs, and an attempt to make a list would just end up being completely dominated by LAB's, HVC's while leaving out the more famous and prototypical representations of nebulae: planetary nebulae and H II regions. There is also a very large gap between the size of the largest entries and the mid to low entries (SSA22 Protocluster is 200 million light-years while the low entries are in the mere hundreds, and not very many entries between); such gaps are not present in the List of largest stars and List of most massive black holes. I've even got myself on such great lengths of time trying to fill out the latter list to avoid having any massive gaps between the entries the size of Sgr A* to the overmassive beasts at the top.


 * And finally, the benefit of both the largest stars and most massive black holes list is that we have large-scale surveys and references available dedicated to the determination of their sizes. Such references are not available for galaxies (hence the problem of the list of largest galaxies) and the same is true for the largest nebulae. While I do see the potential of such a list as being a useful navigational tool, and I do agree that incompleteness does not disqualify a list, we must understand that our problem here is inconsistency - no clear consensus on how sizes of nebulae can be defined. Vast majority of the entries, I believe, are products of self-research as well, and I don't think Wikipedia is the one that should declare what should be and what is not.


 * Moving it to Lists of nebulae instead can solve a few problems; we can just add the nebulae as much as we can without having to worry about what their sizes are. SkyFlubbler (talk) 12:55, 22 July 2021 (UTC)


 * The above discussion is preserved as an archive of the debate. <b style="color:red">Please do not modify it.</b> 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.