View source for Template talk:Infobox galaxy

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==Image Caption issues==
I've noticed that several galaxy articles using this template ([[Aquarius Dwarf]], [[Black Eye Galaxy]], [[Centaurus A Galaxy]], etc.) will repeat the image caption text, and insert it in the first line of the article.  I can't see any reason for this, can anyone fix it, or explain it? [[User:Brendanfox|Brendanfox]] 09:56, 3 January 2006 (UTC)
:Fixed. --[[User:JamesHoadley|JamesHoadley]] 19:55, 3 January 2006 (UTC)
::Cheers, [[User:Brendanfox|Brendanfox]] 23:01, 3 January 2006 (UTC)

==Blank radius in lys shows bad==
If a value for radius_ly is omitted, the template shows {{{radius_ly}}} as the value.  Can someone fix this please? [[User:WilliamKF|WilliamKF]] 01:25, 1 September 2006 (UTC)

== Apparent magnitude ==

In [[Talk:Andromeda_Galaxy#Apparent_magnitude]] the suggestion has been made "In general, it is much easier to find B magnitudes than it is to find V magnitudes, so B magnitudes are generally used in the infoboxes. However, the infoboxes are set up with "(V)" hardwired into them. It might be better just to set up the infoboxes so that the wave band may be specified in the inserted text rather than in the template". Any other views? I shall also post on [[Talk:Apparent magnitude]]. [[User:Thincat|Thincat]] 10:14, 6 June 2007 (UTC)

:This could allow for displaying B and V magnitudes (in two lines) in the infobox.  For example, an entry could be written as "5.5 (B) [line break] 6.5 (V)". [[User:Dr. Submillimeter|Dr. Submillimeter]] 10:32, 6 June 2007 (UTC)

: That seems to be true; the ''B'' magnitude is readily available in scholarly journals whereas the ''V'' magnitude often is not. Can we add a separate row entry for appmag_b? [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 01:03, 12 July 2013 (UTC)

:: As no objection was raised, I added a row for a 'appmag_b' parameter. Hopefully this meets with general approval. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 21:36, 20 July 2013 (UTC)

== Billion usage ==

"Number of stars 200 to 400 billion" - what billion, short (10e9) or long (10e12)?
IMHO "billion" word should not be used because of its two different meanings.  <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/94.253.21.136|94.253.21.136]] ([[User talk:94.253.21.136|talk]]) 17:00, 7 October 2008 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->

== Membership ==

I'd like to suggest adding a row to the infobox for the [[Galaxy groups and clusters|galaxy's group or cluster]] membership. For example, the [[Andromeda Galaxy]] would list [[Local Group]].&mdash;[[User:RJHall|RJH]] ([[User_talk:RJHall|''talk'']]) 18:32, 6 October 2009 (UTC)
: I was "bold" and added a row for the group/cluster membership. I also added a pronunciation row for consistency with the Infobox Planet.&mdash;[[User:RJHall|RJH]] ([[User_talk:RJHall|''talk'']]) 17:28, 11 February 2010 (UTC)

==Stars==
Can we add the number of stars of the galaxy in the template ? [[User:Polylepsis|Polylepsis]] ([[User talk:Polylepsis|talk]]) 15:01, 12 January 2010 (UTC)
: I think it would be easier to get the estimated mass of the galaxy in terms of the [[solar mass]].&mdash;[[User:RJHall|RJH]] ([[User_talk:RJHall|''talk'']]) 17:09, 11 February 2010 (UTC)

== Galaxybox templates ==

Four parameters in the [[template:Galaxybox begin|Galaxybox template set]] that appear to be missing from the Infobox Galaxy template are for the Helio Radial velocity (<code>h_radial_v</code> and
<code>hrv_err</code>) and the Galactocentric Velocity (<code>gal_v</code> and <code>gv_err</code>). Do we want to add those to the Infobox Galaxy template? This would allow the Galaxybox template set to be replaced by the single Infobox Galaxy template.&mdash;[[User:RJHall|RJH]] ([[User_talk:RJHall|''talk'']]) 16:53, 11 February 2010 (UTC)

:Well... the advantage to the galaxybox set is that it allows a custom section to be inserted. WPSHIPS seems to do that with their template set on articles sometimes. But I see no reason not to insert it into the template in any case. The unified-template requires more template-coding skills than the template-set for maintenance issues. (atleast it doesn't look like the complex/hyperlong {{tl|chinese}} ... editing that thing is hard; nor other hypercomplex templates, or hypercomplex template sets (like some of the measurement unit templates) ) [[Special:Contributions/70.29.210.242|70.29.210.242]] ([[User talk:70.29.210.242|talk]]) 08:56, 12 February 2010 (UTC)
==Citations==
The Infobox Galaxy in [[Leo A]] contains a citation, and the citation in turn is causing an error message: Cite error: Invalid <nowiki><ref></nowiki> tag; no text was provided for refs named ned; see Help:Cite error. [[User:Jc3s5h]]
: Okay it is fixed now. Sorry for the problem.&mdash;[[User:RJHall|RJH]] ([[User_talk:RJHall|''talk'']]) 19:42, 13 February 2010 (UTC)

== Incorrect Astronomical Terminology ==

This, like about a billion other Wikipedia Astronomy pages, incorrectly uses the term "epoch" when referring to celestial coordinates.  It is incorrect to use "epoch" when referring to a coordinate system.  The correct term is "[[equinox]]".  For J2000 equatorial coordinate system, J2000 is the equinox not the epoch.  Epoch refers to the timing of an astronomical observation or of a prediction.  The difference is not insignificant for anything that varies with time, is in a short period orbit, or has proper motion.  That may not include galaxies in particular, but we should at least be consistent among objects to avoid the type of confusion everyone seems to be suffering from.[[User:SETIGuy|SETIGuy]] ([[User talk:SETIGuy|talk]]) 03:11, 26 August 2011 (UTC)
: That may as be, but Epoch is the term used on the SIMBAD query pages for the IRCS coordinates. Apparently, Wikipedia is just basing the usage on the sources. If there is a problem, then you'll need to correct it there first. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 16:22, 28 July 2013 (UTC)

==Link to [[Galaxy groups and clusters]]==
I suggest changing the infobox's link "<nowiki>[[Galaxy groups and clusters|Group or cluster]]</nowiki>" to "<nowiki>[[Galaxy group|Group]] or [[Galaxy cluster|cluster]]</nowiki>" to avoid the red link.  -- [[User:Edgar181|Ed]] ([[User talk:Edgar181|Edgar181]]) 13:18, 28 October 2013 (UTC)
:{{done}}. Looks like the change has been made.  Thanks.  -- [[User:Edgar181|Ed]] ([[User talk:Edgar181|Edgar181]]) 10:32, 4 November 2013 (UTC)

== Size ==

Why does the size parameter specify the units (ly), unlike every other item in the infobox? A wholesale change is probably a bad idea, but I think that adding a parameter to remove the unit label and let the units be specified with the number would be better. eg:

Size: 100,000 ly

or

Size: 30 kpc

instead of 

Size (ly): 100,000

Separately, "size" is a poor choice of words in the first place. Do we mean radius? Area? Diameter? Angular or physical? Half-light radius/[[effective radius]]? Full extent of the diffuse halo? Radius of the gas? All of these are entirely valid meanings of "size", so the parameter is very unclear. This has proved to be a significant, months-long issue at [[Talk:IC 1101]]. —Alex ([[User:Ashill|ASHill]] &#124; [[User_talk:Ashill|talk]] &#124; [[Special:Contributions/Ashill|contribs]]) 16:05, 22 January 2015 (UTC)

:Also currently being discussed at [[WT:Astronomy#IC 1101]] (the actual value(s) and associated references, not the template). &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 16:12, 22 January 2015 (UTC)

:In the past I thought about removing the "(ly)" from there. If you see the articles in which the size of the galaxy is mentioned, there is always the ly unit after the value. ''i.e'' Size(ly)= 100,000 ly 

:Besides, I believe "size" is a good word to use. "Size(ly) = 10,000ly in diameter" is often used '''[[User:Tetra quark|Tetra quark]] <sup>([[User talk:Tetra quark|don't be shy]])</sup>''' 16:15, 22 January 2015 (UTC)

::I don't agree. I agree with ASHill. Other templates handle size much more explicitely and {{tl|Infobox galaxy}} can be improved.<sup>[and {{tl|Infobox open cluster}}]</sup> For example,
::*{{tl|Infobox globular cluster}} is most explicit, using {{para|size_v}} (probably grandfathered), {{para|radius_arcminsec}}, {{para|radius_ly}}, {{para|radius_pc}}, {{para|radius_tidal_arcminsec}}, {{para|radius_tidal_ly}}, {{para|radius_tidal_pc}}.
::*{{tl|Infobox astro object}} has both visual and non-visual parameters for apparent size ({{para|appsize_v}} & {{para|appsize_specify}}, both meant to accept a single value) and dimensions (for spherically asymmetric objects, meant to accept LxWxH, etc.).
::*{{tl|Infobox supercluster}} uses {{para|major_axis_mpc}} and {{para|minor_axis_mpc}}.
::Obviously we'd only choose those parameters most frequently used for, and appropriate to, galaxies. ([[Template:Infobox astro object#See also]] has a fairly complete list of all astro templates) &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 16:37, 22 January 2015 (UTC)
:::I agree that the globular cluster infobox is a good model. [[Effective radius]] (or "half-light radius", a term that means the same thing but is more self-explanatory) is probably a good default size quantity to use, and it can be specified in kpc, ly, arcmin, or arcsec. Of course, we'll likely have different size quantities referenced for different galaxies (and different ones are appropriate for different galaxy types), so we'll need a few.
:::It's unclear to me why there are different fields for different units, since the units then have to be specified in the data field anyway (which I think is wise, since it doesn't require editors to go into the template to see which parameter to use for each unit). —Alex ([[User:Ashill|ASHill]] &#124; [[User_talk:Ashill|talk]] &#124; [[Special:Contributions/Ashill|contribs]]) 17:44, 22 January 2015 (UTC)

::::Usually when a unit is specified in a parameter name, it's either because a wikilinked version of the unit appears automatically after the input value, or to nudge editors into using some kind of standard. I personally prefer variants of [[parsec]] over [[light years]], as does most of the astronomical community, especially for objects as distant as other galaxies (though both are equally arbitrary imo). This can be done by specifying both a linear parameter {{para|half_light_radius_kpc}} and an additional angular parameter {{para|half_light_radius_arcminsec}}, for example. In this case, I'd prefer to nudge the editor and not hard-append [[kiloparsec|kpc]]/[[parsec|pc]] and/or [[arcmin]]/sec, and instead suggest using the {{tlx|convert|10|pc|ly|abbr{{=}}on|lk{{=}}on}} template in the infobox documentation (producing: {{convert|10|pc|ly|abbr=on|lk=on}}). Also, now would be a good time to either continue using ly on any new parameters, or to start using kpc, if there's no a good reason for objection. What do you think of these two parameters, and what other dimensional properties besides [[half-light radius]] would be penultimately useful? &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 20:05, 22 January 2015 (UTC)
:::::I prefer parsec as well, but I'm a practicing astronomer, so my opinion is heavily biased by work; I'm not as sure that it's the best for general readership. Prodding towards converting is probably a good idea. Or maybe have two options: an _kpc option which takes kpc as input and automatically puts it into the convert template (so {{para|half_light_radius_kpc|30}} would produce <nowiki>{{convert | 30 | kpc | ly | abbr=on | lk=on}}</nowiki> without the user having to do so manually), and an option without the _kpc which just leaves a free-form field?
:::::I think those parameters are probably good. Maybe also {{para|hi_radius}} and {{para|xray_radius}}. I'm sure there are others that I'm not thinking of off the top of my head. —Alex ([[User:Ashill|ASHill]] &#124; [[User_talk:Ashill|talk]] &#124; [[Special:Contributions/Ashill|contribs]]) 20:51, 22 January 2015 (UTC)

::::::Forcing {{para|half_light_radius_kpc|30}} to put 30 into the {{tl|convert}} template is a slightly less aggressive analog to hard-appending kpc/pc. Dwarf galaxies come to mind, where it might be more convenient to use pc instead of kpc, for example, so we'd need instances with _mpc, _kpc, and _pc to cover both sides of the size-spectrum, which seems excessive. The documentation can have <code><nowiki><!--use {{convert|000|pc|ly|abbr=on|lk=on}} to convert M/k/pc to M/k/ly--></nowiki></code> as a work-around.
::::::For {{para|hi_radius}}, perhaps {{para|h1_radius}} would be more intuitive since "[[H I region|HI]]", in this case "hi", is pronounced "H-one" (I'm writing for the larger audience here).
::::::Are [[H I region|HI]] measurements reported at half-light (or equivalent)? If so, then {{para|h1_half_light_radius_kpc}} would fit the convention we're making. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 22:00, 22 January 2015 (UTC)
:::::::H I (meaning atomic hydrogen) is ''never'' written as H1, and it doesn't really matter if editors mispronounce the name of the template field. So I'd leave it as hi_radius, though it certainly is crummy terminology.
:::::::Reporting of HI sizes suffers from similar inconsistencies as the optical. Putting it cynically, they're probably most commonly reported as "as far out as we can convince the referee we have a detection of hydrogen at our sensitivity". But exponential scale lengths or [[scale height]]s are often used as well (and are probably the most meaningful number to report, though they give a much smaller headline number than either a half-light radius or the "as far as I can see emission" radius). Half-light radius isn't used very much because a [[de Vaucouleurs profile]] doesn't really describe HI well in most cases (I think). So probably add {{para|hi_scale_length}} or {{para|h1_scale_length}} with _kpc and _pc, and maybe _arcminsec. —Alex ([[User:Ashill|ASHill]] &#124; [[User_talk:Ashill|talk]] &#124; [[Special:Contributions/Ashill|contribs]]) 03:04, 23 January 2015 (UTC)

::::::::That's fine; both have their pros and cons. If anything, it will entice editors to read the documentation, ha.
::::::::Using separate parameters for _pc and _kpc seems excessive, ''unless'' you like the idea of putting the value into a hard-coded {{tl|convert}}. Otherwise, since pc is the root, we can go with that. Either way, the documentation will make it obvious that M/k/pc is at the editor's discretion, or if it's required to be _pc or _kpc.
::::::::So, so far we have:
::::::::*{{para|half_light_radius_pc}} (possibly +_kpc)
::::::::*{{para|half_light_radius_arcminsec}}
::::::::*{{para|hi_scale_length_pc}} (possibly +_kpc)
::::::::*{{para|hi_scale_length_arcminsec}}
::::::::*{{para|xray_radius_pc}} (possibly +_kpc)
::::::::*{{para|xray_radius_arcminsec}}
::::::::&nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 04:40, 23 January 2015 (UTC)
:::::::::I think that's a good-looking list of parameters to add. Do you have the template expertise to do this? —Alex ([[User:Ashill|ASHill]] &#124; [[User_talk:Ashill|talk]] &#124; [[Special:Contributions/Ashill|contribs]]) 18:45, 26 January 2015 (UTC)
::::::::::[https://en.wikipedia.org/w/index.php?title=Template:Infobox_astro_object&action=history Yes :)] &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 19:25, 26 January 2015 (UTC)

{{outdent|8}}{{tl|Galaxybox begin}} (made in 2008) seems to duplicates some of {{tl|Infobox galaxy}} (made in 2004), but I'm not sure why there're 2. First we should figure out which is meant to supersede the other, if at all. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:17px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[Special:Contributions/Tom.Reding|contribs]] ⋅[[WP:Don%27t-give-a-fuckism|dgaf]])</span>&nbsp; 17:28, 26 January 2015 (UTC)
:For what it's worth, galaxybox begin is trancluded [https://en.wikipedia.org/wiki/Special:WhatLinksHere/Template:Galaxybox_begin 36 times]; infobox galaxy is trancluded [https://en.wikipedia.org/w/index.php?title=Special:WhatLinksHere/Template:Infobox_galaxy&limit=500 648 times].

::It seems that I've forgotten about this... I'll try to get to this this month, unless someone beats me to it. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 02:21, 2 February 2016 (UTC)

:{{tl|Galaxybox begin}} still transcluded 36 times, and {{tl|Infobox galaxy}} now transcluded 796 times. {{tl|Galaxybox begin}} should be migrated. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 15:59, 14 May 2016 (UTC)

::I wanted to perform this migration first before adding these new parameters, but it seems that I need to add these parameters first, since {{tl|Galaxybox observe}} has more explicit size-parameters than {{tl|Infobox galaxy}} (for now).

::{{U|Ashill|ASHill}}, reapproaching this (after over a year), and having done a LOT of [[User:Tom.Reding/JPL to Infobox planet|meticulous]] updating on {{tl|Infobox planet}}s for [[minor planets]] in the meantime, it's clear to me that having {{para|&#42;_kpc}} etc. params is extremely restricting, especially when multiple values & multiple references are desired for each param. So a free-form field is really the only option, relegating <code><nowiki>{{convert|...|kpc|ly}}</nowiki></code> to the documentation's comments. So instead of {{para|half_light_radius_pc}} etc., I think a free-form field named {{para|half_light_radius_physical}} is better. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 17:17, 14 May 2016 (UTC)
::Or {{para|half_light_radius_pc}}, as long as it's freeform. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 17:55, 14 May 2016 (UTC)
:::6 parameters & a new heading, "Characteristics", have been added to [[Template:Infobox galaxy/sandbox]]. I think the next steps should be:
:::# Agree on parameters & make sandbox live (obviously). <small>({{Done}} &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 19:57, 30 September 2016 (UTC))</small>
:::# Migrate all existing {{para|size}} & {{para|size_v}} into these new, more descriptive parameters.
:::# Deal with/see what remains (possibly make an additional, unforeseen parameter or 2).
:::# Either deprecate {{para|size}} & {{para|size_v}}, or save them as a catch-all parameter for other wavelengths (i.e.: {{para|size_pc_specify|xx kpc (FUV)}} & {{para|size_arcminsec_specify|x.xx&deg; (FUV)}}).
:::&nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 19:53, 14 May 2016 (UTC)

==Surface Brightness==

I suggest the inclusion of this row into the template, which is an important parameter for observational astronomy, as it directly relates to how easy (or difficult) the visual observation of an extended object (non point-like) can be.
As it is shown in [[Surface Brightness]], it can be calculated via the formula <math> S = m + 2.5 \cdot \log_{10} A </math> <br />
(and the entries for most galaxies already display their respective dimensions) or outsourced from trustworthy, established references, such as Roger Clark's "Astronomy of the Deep Sky" ([https://books.google.com.br/books?id=gCI9AAAAIAAJ&lpg=PA133&pg=PP1#v=onepage&q&f=false ISBN:0521361559]) (Maringaense 12:50, 3 April 2016 (UTC))

:{{U|Maringaense}}, I added {{para|sbrightness_specify}} to [[Template:Infobox galaxy/sandbox]]. There'll be a large update soon, so comments on the sandbox version are welcome. &nbsp;&nbsp;<b>~</b>&nbsp;<span style="font-family:Monotype Corsiva; font-size:16px;">[[User:Tom.Reding|Tom.Reding]] ([[User talk:Tom.Reding|talk]] ⋅[[WP:DGAF|dgaf]])</span>&nbsp; 20:03, 14 May 2016 (UTC)

== The documentation for this template is ''terrible'' ==

Please explain what these parameters are and what physical quantity should be in those. It's completely obscure and nearly impossible to use. <span style="font-variant:small-caps; whitespace:nowrap;">[[User:Headbomb|Headbomb]] {[[User talk:Headbomb|talk]] / [[Special:Contributions/Headbomb|contribs]] / [[WP:PHYS|physics]] / [[WP:WBOOKS|books]]}</span> 16:09, 5 July 2016 (UTC)

== Images in different wavelengths ==

Might this be adjusted somehow incorporate multiple images of the galaxy at different wavelengths?  I'm imagining a banner image that's either the most arguably aesthetic image, and at the bottom the format may have six spacers for an image of each: Radio, Infrared, Visible, UV, X-Ray, and Gamma Rays.  (maybe more?)

This could help make this information more immediately accessible, and also highlight what galaxies <i>haven't</i> yet been imaged at which wavelengths. --<b><span style="color:#00A86B;">[[User:Thisisbossi|Bossi]]</span></b> (<small>[[User talk:Thisisbossi|talk]] • [[:commons:User:Thisisbossi/Gallery|gallery]] • [[Special:Contributions/Thisisbossi|contrib]]</small>) 15:37, 31 May 2019 (UTC)

== Name field ==

Contradicting the documentation, this template does not actually insert the page name if you leave the {{para|name}} field empty. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 20:17, 23 December 2021 (UTC)

== The sizes of galaxies ==

Can someone modify this template to include more specific criterion for diameters and all? There are 11 of them listed [http://leda.univ-lyon1.fr/a106/fields.html#a106/dcode here] in HyperLEDA. Because this is the main way how galaxies are measured, and the current ones in place (like the X-ray diameter) is not used by a long shot by anyone. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 15:59, 29 August 2022 (UTC)

I am reviving this discussion in order to get the attention from [[WP:AST]]. Basically, both H I scale length and X-ray radius used in the current template is rarely used in astronomy. My proposals are the following:

* Add some of the 11 diameter standards in HyperLEDA (this is also used by NED).

* Retain the half-light radius, but change its subnote from whether it is physical or apparent to its wavelength or some variation of it (70% and 90% also used by HyperLEDA and NED).

* Add the isophotal diameters (D25, Holmberg isophote, 25.5 or 27 (used by ESO/Uppsala).

* Also add the total aperture diameter and 20 mag/arcsec used by 2MASS and R25 used by SDSS.

Unlike the present ones (which are very rarely used), the ones I mentioned can be easily retrieved from NED. It would also help as to remove the clumsy note I added to some galaxies (like the [[Andromeda Galaxy]] specifying the D25) by instead letting it be a standard format in this template. Comments? [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 14:56, 28 December 2022 (UTC)
: SIMBAD just lists the galaxy's angular size with the spectral band in parentheses.[http://simbad.cds.unistra.fr/guide/sim-id.htx] Wouldn't that be sufficient for most encyclopedic purposes? We could always set it up in a manner comparable to the appmag fields of the {{tl|Starbox character}} template, allowing multiple dimensions to be listed, each with its own enumerated passband parameter. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 01:50, 4 January 2023 (UTC)
::Yep, but I am more leaning to use the NASA/IPAC Database rather than SIMBAD for data about galaxies. Although they do list the spectral band in the angular sizes, the NASA/IPAC Database goes much further by listing the method being used, the particular wavelength, the angular size with respect to different methods, and even cites the source where it comes from. See for example [https://ned.ipac.caltech.edu/byname?objname=Messier+31&hconst=67.8&omegam=0.308&omegav=0.692&wmap=4&corr_z=1 this one] for the Andromeda Galaxy and clicking the "Diameter" tab. I also do not recommend just using the angular diameter and do your own math from there, as you cannot retrieve what specific brightness threshold was used to identify the angular diameter. The classic NASA/IPAC Database version even has a note warning that angular diameters are unreferenced. To be consistent, let us use these standards, plus we can also further cite the study that made the diameter listed (in the case of Andromeda, the RC3). [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 14:24, 5 January 2023 (UTC)
::: How is that inconsistent with my suggestion? I don't think we need new parameters for every possible method. Just use one consistent general approach, so there is less confusion for the reader. Anyway I've said my piece: I'm not a fan of the current approach of listing things such as "half-light radius" and "X-ray radius". What will those even mean to the average reader? [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 21:50, 5 January 2023 (UTC)
::::I'm not saying we should list every possible method, but to modify the template to include methods that are at least based on the principle on how they were measured. There is no single "consistent general approach" in the astronomical literature in defining galaxy sizes, but as far as I can tell we can settle for at least three or four ways (isophotes, half-light and variations, 2MASS and possibly scale length), all of which are widely used and can be retrieved easily. Some galaxies have data for all of them, some fewer, and some at least one (2MASS which is all-sky). But I expect that 99% would be well-covered by those four methods (2MASS is all-sky, after all). 

::::Even then there are still further variations to those methods that we also have to address (D25, Holmberg, and D27 for isophotal as well as 70% and 90% for half-light radius) which we can easily do so. We can change "'''half-light radius (physical)'''" and "'''half-light radius (apparent)'''" to something like "'''half-light radius (R<sub>50</sub>)'''", "'''70% light radius (R<sub>70</sub>)'''", and so on. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 22:15, 5 January 2023 (UTC)
::::: Perhaps you're misinterpreting my proposal? The point of a flexible approach is that you can list as many or as few as needed. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 22:00, 7 January 2023 (UTC)

:::::: Oh, I see. In that case, we should still change thr infobox to account for methods that are actually used, and then remove the current " X-ray radius" which I am pretty sure is not actually used by any article. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 10:14, 9 January 2023 (UTC)

:::::Is it possible to calculate the sizes of galaxies using all known methods, and may I help you?--[[User:The Space Enthusiast|The Space Enthusiast]] ([[User talk:The Space Enthusiast|talk]]) 17:01, 6 January 2023 (UTC)

== "Size" is ambiguous ==

The use of the word "size" makes it unclear if it is referring to radius, diameter, or something else entirely. It can be possible to infer the definition used from an actual galaxy page, but it should still be made 100% clear in the infobox. <span style="font-family:times;background-color:black;padding:2px 3px 2px 3px">[[User:Nussun05|<span style="color:#ffc08c">VY Canis Majoris</span>]]</span> ([[User talk:Nussun05|talk]]) 07:23, 11 January 2023 (UTC)
:I agree.—[[User:The Space Enthusiast|The Space Enthusiast]] ([[User talk:The Space Enthusiast|talk]]) 23:45, 12 January 2023 (UTC)

== We need to be more specific on "size." ==

I think I did a poor job in discussing this topic a year ago. So let me restate it.

'''Almost no one''' uses H I scale length or X-ray radius for galaxy sizes. As far as I am aware scale lengths are used to make models on star distribution, not determining physical diameters.

We should change the infobox parameters and incorporate the standard D<sub>25</sub> and half-light radius variants. Those are what NED uses for galaxy diameters, and those are what most astronomers use. And frankly it is much better to have the method stated built-in on the infobox so that we can just add the numbers in there.

There. I hope that is much more clear and straight to the point. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 18:02, 27 March 2024 (UTC)

:Can you please be specific? Which lines of the template would you remove and what would be added? [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 18:35, 27 March 2024 (UTC)
::Like I said, the "H I scale length" and "X-ray radius" currently in the infobox can be replaced by the following:
::* D<sub>25</sub> isophotal diameter (some like ESO using 25.5, 26, and 27).
::* K<sub>20</sub> isophotal diameter
::* Total aperture diameter
::* 50% B-band diameter, with variants like 70%, 80%, and 90% (though I prefer just to add the 50% and 90%).
::Check [https://ned.ipac.caltech.edu/cgi-bin/datasearch?search_type=Diam_id&objid=58143&objname=NGC%200253&img_stamp=YES&hconst=67.7&omegam=0.27&omegav=0.68&corr_z=1&of=table this sample] of diameters for the Sculptor Galaxy for the reference levels. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 01:27, 28 March 2024 (UTC)
:::I broadly agree with your goal, but this level of detail is not, in my opinion, suitable for wikipedia. I think the galaxy "diameter" should be given in distance units (ly) in one way, not 4 ways. D<sub>25</sub> or if not available, K<sub>20</sub>, etc. We are not database. The reader should quickly get a valid understandable value and a reference for more details.
:::What we don't want is to end up with something like NED page you linked. However valuable that may be to an astronomer is has no value for a wikipedia reader. To be honest I couldn't see how it bolsters your case since it does not seem to have "diameter" and the closest thing is major axis in arcsec. That means that an editor needs to be quite expert to update the template values. Is that what we want?
:::I don't want to be negative, I'm just trying to give an opinion as non-expert interested editor. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 01:58, 28 March 2024 (UTC)
::::"but this level of detail is not, in my opinion, suitable for wikipedia."
::::A counterargument I have on this one is what happened to the Milky Way and Andromeda galaxies, where recent sizes of 150k light years all the way to 200k was done on the basis of "disk stars" from Gaia DR2. This has primarily been enforced by Wikipedia, which used that number from 2016 to 2022.
::::This should change, because people have this impression that this is how galaxy sizes are measured. It isn't, and for decades we have been using the methods I have mentioned.
::::Putting them as infobox parameters would make it less ambiguous, and would make it less likely for cases like the Milky Way to happen again in the future, where people just shove in some number and cite some news which, for the most part, are just hyping up numbers and sacrificing scientific accuracy for clicks and engagement. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 08:03, 28 March 2024 (UTC)
::::"since it does not seem to have "diameter" and the closest thing is major axis in arcsec."
::::You have a major axis in arcsecond (the apparent size). You use trigonometry along with distance, and you get the physical diameter.
::::See [https://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=NGC+253&extend=no&hconst=67.44&omegam=0.268&omegav=0.684&corr_z=1&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES this NED entry] for the Sculptor Galaxy at "Quick-Look Angular and Physical Diameters", where they place the physical diameters (axes) of the galaxy. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 08:09, 28 March 2024 (UTC)
::::''"I think the galaxy "diameter" should be given in distance units (ly) in one way, not 4 ways. D25 or if not available, K20, etc. We are not database."''
::::We can impose a rule like one entry per galaxy or so. It should be noted that I am advocating to add them because many entries of galaxies in NED do not have D<sub>25</sub> diameters available, just K<sub>20</sub> or others. Having them (I prefer just three: D<sub>25</sub>, K<sub>20</sub>, and 90% B light diameter) should at least make it open and have more choices if one is not available.
::::''"However valuable that may be to an astronomer is has no value for a wikipedia reader."''
::::I don't think this mind-reading fallacy is a valid argument here. Of course it would be valuable to be more specific, both to an expert and to a reader. I don't think this case of simply stating what method is used built-in on the infobox is overly and unnecessarily specific, as stated in my previous example in the Milky Way where ambiguity arose because we are not very specific.
::::''"That means that an editor needs to be quite expert to update the template values. Is that what we want?"''
::::Yes! You should be well-informed and know what you are doing before you update the template values. You should have a reference to back it up, and should not be pulling some strings out of sensationalist astronomy "news" references. Because this is a science. As simple as that. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 08:22, 28 March 2024 (UTC)
:::::Thank you for this detailed reply. You've convinced me that your proposed solution is not appropriate. We should look for some other solution to your issue.
:::::* "Because this is a science." 
:::::Every scientific topic has great depth and detail that is not appropriate to write about on Wikipedia.
:::::Explaining how galaxies are measured, what NED means and the significance of its data, why some galaxies have some measurements and not others, why the Xray radius and H I scale length are not appropriate and so on are all great things to cover in Wikipedia. A detailed discussion of the values for say 3 or 4 representative galaxies would also be appropriate. 
:::::Cataloging data that astronomers would not use (they would use NED) and readers can't understand ("You should be well-informed and know what you are doing") is not appropriate in my opinion. We don't have enough expertise to build and maintain a database to match your goals and the cost in editor-time would be taken from more effective ways of improving astronomy content. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 15:15, 28 March 2024 (UTC)
::::::''"Cataloging data that astronomers would not use (they would use NED) and readers can't understand ("You should be well-informed and know what you are doing") is not appropriate in my opinion. We don't have enough expertise to build and maintain a database to match your goals and the cost in editor-time would be taken from more effective ways of improving astronomy content."'' 
::::::I really don't get this idea. It's like saying to be lazy and stick to the usual content because "readers can't understand it." Using that logic then we should remove RA and Dec, galactocentric and heliocentric radial velocity on the infobox because who the eff on the normal readers uses it anyway?
::::::By the way, ordinary people would definitely use D<sub>25</sub> isophotal diameters if they know what ut is. Saying "readers can't understand" this topic is more of an insult to the reader rather than a compliment to wind things down. We must showcase data that tailors to the normal readers while respecting the experts in the field.
::::::''"We don't have enough expertise to build and maintain a database to match your goals..."''
::::::Which is why we have references in Wikipedia for a reason. We will give references to the numbers, preferably on NED. I don't believe that is too hard and the "cost in editor time" would be just three clicks away in searching the object in NED and clicking the "Diameter" tab.  [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 16:42, 28 March 2024 (UTC)
:::::::I'm confused about your point of view. Earlier you said expertise is needed before using NED. Now you say it's easy. 
:::::::I'm advocating focusing on knowledge, not data. Your idea to "remove RA and Dec, galactocentric and heliocentric radial velocity on the infobox" also sounds good to me. These are not notable for every galaxy. Extra-ordinary values or values of historic interest should be discussed in the article on the galaxy. 
:::::::Let me put to you this way: are you personally prepared to update all of the existing values and maintaining them going forward? [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 16:54, 28 March 2024 (UTC)
::::::::''"Your idea to "remove RA and Dec, galactocentric and heliocentric radial velocity on the infobox" also sounds good to me."''
::::::::That is enough for me to be convinced that you don't have any knowledge of this subject. Removing RA and Dec is basically removing information about the location of the object in the sky. This data is '''essential''' and to tell me that "readers can't understand it" makes me think your idea of a Wikipedia reader is an eight year old kid.
::::::::''"Extra-ordinary values or values of historic interest..."''
::::::::is not definitive to the physical diameter, RA and Dec, heliocentric velocities. Because these are intrinsic properties of every object. Using your logic we should remove the numbers on [[Earth]]'s infobox because these are "extra-ordinary values."
::::::::''"I'm confused about your point of view. Earlier you said expertise is needed before using NED. Now you say it's easy."''
::::::::I hate to bring it to you but that is not what I said. What I said is that "''You should be well-informed and know what you are doing before you update the template values."'' Being ''"well-informed"'' means you have the reference at hand to update and change the values. It is a separate topic on how easy/hard it is to use NED. By the way, I am confident that any galaxy-focused editor in the Wikiproject can use NED. It is a standard reference used all over these years.
::::::::Before we stray into the topic further, I have rebutted the claims that the changes I propose will be a hard deal for editors to catch up on. The issue here is standardization and to avoid mistakes like what happened in the Milky Way in the future. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 05:39, 29 March 2024 (UTC)

: There are other parameters that need discussion, such as 'mass' and 'stars'. Papers don't publish a 'mass', they publish stellar mass or neutral hydrogen mass or dust mass. Likewise, they don't publish a number of stars, they list stellar mass. [[User:Praemonitus|Praemonitus]] ([[User talk:Praemonitus|talk]]) 22:55, 27 March 2024 (UTC)
:Counter proposal: just delete the  H I scale length or X-ray radius entries in the template. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 15:16, 28 March 2024 (UTC)
::That is my proposal, delete those ''and'' add the D<sub>25</sub> physical diameters and 90% B light as replacements. You should not remove information about diameters - those are the sizes of objects for crying out loud. [[User:SkyFlubbler|SkyFlubbler]] ([[User talk:SkyFlubbler|talk]]) 05:41, 29 March 2024 (UTC)

== Wikidata awareness ==

Would there be interest in making this template able to read certain properties from Wikidata? There seem to be many related properties on Wikidata (see [[:wikidata:Wikidata:WikiProject Astronomy/Properties|Wikidata:WikiProject Astronomy/Properties]]) which could map into the infobox fields. If anyone is interested in helping then please let me know, because I have no expertise in galaxies &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 11:50, 18 June 2024 (UTC)

== Extended-confirmed-protected edit request on 22 November 2024 ==

{{edit extended-protected|Template:Infobox galaxy|answered=yes}}
Two things:
# Disambiguate three links to [[magnitude]], to (IMO) [[Magnitude_(astronomy)]]
# Change  <code><nowiki>| label15 = [[Absolute magnitude]]&nbsp;<small title="in visual light">(B)</small></nowiki></code> to <code><nowiki>| label15 = [[Absolute magnitude]]&nbsp;<small title="in B band">(B)</small></nowiki></code> because it's an obvious typo. [[User:Milo8505|Milo8505]] <sub>[[User_talk:Milo8505|(talk)]]</sub> 18:31, 22 November 2024 (UTC)
:[[File:X mark.svg|20px|link=|alt=]] '''Not done for now''': please establish a [[Wikipedia:Consensus|consensus]] for this alteration '''[[Wikipedia:Edit requests|before]]''' using the {{Tlx|Edit extended-protected}} template.<!-- Template:EEp --> I got #2 and #1 was already fixed. [[User:Skynxnex|Skynxnex]] ([[User talk:Skynxnex|talk]]) 20:03, 22 November 2024 (UTC)
::Maybe I'm missing something about Wikipedia, but I think it has already been fixed?
::Did I do a wrong edit request? I believe both changes I asked were simple maintenance changes. [[User:Milo8505|Milo8505]] <sub>[[User_talk:Milo8505|(talk)]]</sub> 10:47, 23 November 2024 (UTC)
:::@[[User:Milo8505|Milo8505]] oops I somehow managed to click the wrong template. Your request was fine. The rest of my answer is accurate. This is {{done}}<!-- Template:EEp -->. Thanks for noticing them. [[User:Skynxnex|Skynxnex]] ([[User talk:Skynxnex|talk]]) 12:51, 23 November 2024 (UTC)
::::Thank you very much, don't worry! [[User:Milo8505|Milo8505]] <sub>[[User_talk:Milo8505|(talk)]]</sub> 14:27, 23 November 2024 (UTC)