Talk:Bedin I

Unsigned comment

Member of the Local group at 10 Mpc? LOL Mike — Preceding unsigned comment added by 37.77.113.121 (talk) 11:09, 1 February 2019 (UTC)

Local Group

Dear PhilipTerryGraham, given that I'm not a Wikipedia formatting specialist, I'm a specialist in dwarf galaxies (let me keep my anonymity with a generic Mike). Declaring that this galaxy is "a member of the local group", would mean that we should rewrite decades of study ... The same Wikipedia article [1] expresses well and correctly the knowledge to about. An object like Bedin I at about 10Mpc may never have had any involvement with the galaxies of the group and, frankly, it is not even as special as some releases say. Just read the original paper on MNRAS to catch the doubts. For example it is ancient, of course, but like so many other dwarf spheroidal (indeed it is the norm). Is it really "the most isolated galaxy"? There are many things to discuss about it. In any case, the fact that it is prospectively aligned with the globular cluster (very close to the Milky Way), does not promote an object in the Local Group. In other words, it is only a background galaxy of as many as 30 million light years! About the objects of the Local Group, again recently - here I am also sibylline - the Donatiello I dwarf galaxy was discovered. This is really a candidate of the Local Group at just 3 Mpc (10 million light-years), although peripheral . About this interesting object, just as old, but above all close (about 120 ° in the list of the closest to the Milky Way) has not written anything ... because it was discovered by an amateur! Here the press release: http://www.iac.es/divulgacion.php?op1=16&id=1486&lang=en Being practical, can you deal with it? Thank you. Mike — Preceding unsigned comment added by 176.32.16.18 (talk) 10:51, 2 February 2019 (UTC)

@176.32.16.18: Hey there, Mike! This Gizmodo article was cited in the “Characteristics” section that Bedin I is a member of the Local Group; Luigi Bedin, the discoverer, even explicitly states that it is a member of the Local Group in that citation, saying “Had the galaxy been 10 times further away, it would have been much harder to detect, [...] It would’ve been outside our Local Group.” This ultimately led to Bedin I being described as such here. An article written for the European Space Agency’s Hubble website described Bedin I as “possibly the most isolated small dwarf galaxy discovered to date”, and thus was cited for the claim of it being one of the most isolated dwarf galaxies known. – PhilipTerryGraham (talk · articles · reviews) 15:07, 2 February 2019 (UTC)

Comment on comment, page edited

OMG. I read the front page, thought, "no way is this a member of the local group if it's 10Mpc away and associated with another non-Local Group Spiral Galaxy." I went to read the Talk page. Yes! Somebody who knows something has pointed it out. But. The response is that you can't point things out unless you learn a bunch about Wikipedia-specific commenting formats.

Wikipedia is in trouble if people who know things aren't able to point out problems and have them acted on without first going through learning even a small amount of gratuitous extra process.

I just edited the page myself, and took out the reference to the Local Group. Fortunately, that seems to have worked. I hope it sticks.

(I am not a specialist in dwarf galaxies like Mike, but I am a professional astronomer.) Rknop (talk) 14:40, 2 February 2019 (UTC)

@Rknop: It seems a contradiction has arisen here, as Luigi Bedin himself has described the galaxy as part of the Local Group, which is why it was described as such here. This is less a problem about Wikipedia and more about professional astronomers saying things contrary to one another, and editors such as myself being caught up in the confusion... – PhilipTerryGraham (talk · articles · reviews) 15:07, 2 February 2019 (UTC)

@PhilipTerryGraham: Where does Bedin say it's in the local group? The MNRAS paper doesn't say that. It does say it's a member of the "local universe", but that's not the same thing. "Local universe" is a more vague term than local group. The Local Group is the group of galaxies associated with the Milky Way and the Andromeda Galaxy, plus a few other small galaxies that are all within a couple Mpc of those two primary galaxies (and the Triangulum Galaxy, if you want to consider that one a big galaxy as well). The "local universe" refers to the Universe as it is today, and depending on usage can include anything within several million to even several hundreds of millions of light years. Rknop (talk) 15:12, 2 February 2019 (UTC)

@Rknop: This Gizmodo article was used to cite the claim of the galaxy being in the Local Group in the “Characteristics” section of the article. The author writes “At 30 million light-years away, it’s considered part of our Local Group of galaxies.” and Bedin is quoted as saying “Had the galaxy been 10 times further away, it would have been much harder to detect, [...] It would’ve been outside our Local Group.” – PhilipTerryGraham (talk · articles · reviews) 15:20, 2 February 2019 (UTC)

@PhilipTerryGraham: Ah, OK. That's actually not a quote from Bedin, and the author of that Gizmodo article (George Dvorsky) is wrong. Here is a Bad Astronomy article (Phil Plait is a very reliable source for all things astronomical) which gets it right: "he astronomers determined that Bedin I is about 28 million light years away. That's close, relatively speaking, though well outside the Local Group of galaxies which holds our Milky Way, Andromeda, and a couple of dozen other galaxies." (Although Phil isn't fully right here; there are more than a couple of dozen known galaxies in the Local Group nowadays. Because these dwarf spheroidal galaixes are so dim and have such low surface brightness, we keep finding new ones in big surveys.) Rknop (talk) 15:24, 2 February 2019 (UTC)

@Rknop: The article literally says “said Bedin”, however, and Plait’s article has already been used to cite various passages. – PhilipTerryGraham (talk · articles · reviews) 15:33, 2 February 2019 (UTC)

Notes for GA reviewer

To the person who reviews this article under the good article criteria, I'd like to state my preference that each point you make about the article be numbered and distinguished using coloured text, with templates such as {{xt}} or {{!xt}}. This way, I can reference which numbered points I am attending to in my edit summaries, and our replies to each point on the review can be distinguished from the topic/point itself. I believe this would make things much easier and better streamlined for the both of us! See Talk:Planetary Missions Program Office/GA1 and Talk:Music of Rocket League/GA1 for how this can be done! Thanks for understanding! :) – PhilipTerryGraham (talk · articles · reviews) 02:25, 2 February 2019 (UTC)

GA Review

This review is transcluded from Talk:Bedin I/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Sam-2727 (talk · contribs) 00:57, 11 August 2019 (UTC)

This will probably take me 4 to 5 days to do. Sam-2727 (talk) 00:57, 11 August 2019 (UTC)

• "It is situated behind the globular cluster NGC 6752, though is around 28.38 million light-years from Earth." The though suggests that there is some kind of contradiction.

 Done – the sentence has been changed to "It is situated 28.38 million light-years from Earth, behind the globular cluster NGC 6752." – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• when the lead says that Bedin I "is one of the most isolated dwarf galaxies known," that might be overselling it a bit. After all, when this information is presented in the body, it is presented as simply hypothetical. So I would add "possibly" here.

 Done – the opening of the sentence was changed to "Bedin I is possibly one of..." – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• The sentence "Bedin I is also possibly the most isolated dwarf galaxy known, located around 8.7 megaparsecs, or around 28.38 million light-years, from Earth, and at least 650 kiloparsecs, or 2.12 million light-years, from its nearest neighbor, the intermediate spiral galaxy NGC 6744; the Milky Way and Andromeda galaxies are separated by a similar distance" is quite lengthy for a sentence with a semicolon. Could the semicolon be changed to a period? On another note, is it really necessary to provide the conversion from parsecs to light-years? It might be best to just stick with one unit (I would go with parsecs since that is in the infobox). Also in this sentence (sorry, I have a lot to say about this particular sentence), I think the part about the distance from earth should be moved to a separate sentence as well. After all, if the start of the sentence suggests that the sentence will talk about the isolation of Bedin I, then the distance from Earth isn't really necessary to include.

 Partly done – information on the galaxy's distance from Earth has been moved to the opening passage of "Characteristics". However, light-year distances are being kept here – it's vital for readers who don't know what a parsec is, and saves them the trouble of having to convert for themselves. Parsecs are used in the inbox, because the original data from Bedin et al. was presented in parsecs, and thus the original data is placed in the infobox. Placing a second unit of measurement in the infobox for the same cell would be infobox bloating, in my view. – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• "Bedin I measures around 20 by 8 arcseconds across from the point of view of Earth". Isn't it a bit clumsy to mention that its angular size is from the point of view of Earth? Clarity is important, but what else would the angular size be from the point of view of?

 Done – redundant wording removed as suggested. – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• "The galaxy is situated behind a group of unnamed foreground stars within the globular cluster NGC 6752." NGC 6752 is already hyperlinked in the lead.

 Done – duplicate wikilinks to Dwarf spheroidal galaxy, Globular cluster, Hubble Space Telescope, NGC 6744, NGC 6752, Pavo (constellation), and White dwarf per the manual of style. – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• "A second program of 40 orbits, GO-15491, is currently scheduled for late 2019." Maybe clarify that the new program is to further survey the area of NGC 6752 and Bedin I. Also, I'm not sure if the quote given for citation [25] says that the second program is GO-15491. You might need a new citation for this (a good place would be the end of the first paragraph of the observations section of that paper)

 Done – a proper citation to the relevant paragraph in Bedin et. al has been used to cite this passage, as suggested. – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

• "A physical association with NGC 6744 has been speculated however, despite its distance." It would be good to clarify how a physical association is speculated. i.e. because of the close angular seperation and relatively similar distances (although the quote of the citation would have to be extended).

 Done – the sentence has been extended to "A physical association with NGC 6744 has been speculated however, due to the close angular distance between the galaxies, and their similar physical distances from Earth", with the citation quote extended accordingly to verify the claim. – PhilipTerryGraham (talk · articles · reviews) 08:40, 11 August 2019 (UTC)

On second thought, I'll most likely have this done by the end of tomorrow. (I just need to do a second pass of the article and check the citations more thoroughly-- shouldn't take long)

• minor comment, that I'm not even sure needs to be corrected. For the first article in the sources section, the publication date you put is march 2019, but on the mnras website, it is 10 January 2019. Is march the date that entire issue of the journal was published and not just that article?

 Done – the date was the publication of the issue, though it should be the first publication of the article. This has been corrected. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

• For note a, I don't see any evidence from the citations that the field of view is actually 1x1 arcminutes.

 Done – this issue has been resolved by reusing the "hubblesite-1" citation, which quotes "Image is about 1 arcmin across", to properly cite this passage. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

• how does citation 9b support a part of that sentence? I don't see anything about Bedin I's distance in that citation

? Clarify – neither uses of citation 9 seem to involve the issue you describe, though I suspect this issue has been solved anyways on the next point below. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

Yes it is now corrected. Sam-2727 (talk) 14:25, 12 August 2019 (UTC)

• "Bedin I is an isolated dwarf spheroidal galaxy located around 8.7 megaparsecs, or around 28.38 million light-years, from Earth". In the three citations given, I find no reference to its distance from Earth.

 Done – this seems to be an error with multi-citations on my part. I have corrected this by moving up a harvard citation that I had forgotten to use, which quotes "8.7 ± 0.5−0.7 Mpc" as the distance. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

• In the characteristics section, would it be informative to add its average metallicity of around -1.3? (since you already have it in citation 13 and you already discuss metallicity briefly)

 Done – the information has been added as suggested, with the opening of the relevant passage now reading, "At a metallicity of −1.3, the galaxy's population is made up of metal-poor red giant stars..."

• " making it one of the oldest galaxies known." While the citations do discuss it nearly being as old as the universe and how that's weird, none of them state that it is one of the oldest galaxies (indeed, there are actually quite a few galaxies older than it). I know I said just say possibly before, but I would try to at least find a citation to back up this statement or modify it to make the correlation to almost being as old as the universe (mentioned in the syfy article)

? Clarify – I don't understand why it isn't correct to say that it's one of the oldest galaxies known. The article isn't saying it is the oldest galaxy known. I'd like some clarification on what exactly, in the English language, is the essential difference between calling a galaxy "as old as the universe itself" and "one of the oldest galaxies", because they say very similar things in my view. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

It's very slight, but I think one of the oldest galaxies suggests that there are very few galaxies that old, while actually there are quite a few galaxies that have been hypothesized to be that old (and older-- see List of the most distant astronomical objects). But this is a minor comment, so I'm just going to go ahead and close the review and you can change it if you feel it to be necessary. Sam-2727 (talk) 14:25, 12 August 2019 (UTC)

• "Bedin I was accidentally discovered by a team researching white dwarfs in the cluster in an effort to better determine its age." I would change to "the age of NGC 6752" as I had to look into the citations to figure out that it was actually NGC 6752 being referred to.

 Done – the clarification was made, though instead as "...white dwarfs in the cluster in an effort to better determine the cluster's age." – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

• NGC 6752 is listed in the article as the 5th brightest globular cluster in the sky (and the citation supports this), but many other sources point to it being the third brightest in the sky. I think this source might be incorrect.

 Done – the discrepancy was corrected by adding an additional citation courtesy of Astronomy Picture of the Day, and the passage being rewritten to the more neutral "...one of the brightest globular clusters in the sky..." – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

• One last comment-- it might be nice to add links to Bedin I from more pages. While not required by GA criteria, it would be nice to maybe include it in the DSO section of pavo.

 Done – a wikilink was added in Pavo (constellation) as requested. – PhilipTerryGraham (talk · articles · reviews) 09:03, 12 August 2019 (UTC)

Sam-2727 (talk) 14:03, 11 August 2019 (UTC) final check of six criteria:

well written: syntax errors fixed, now good throughout

verifiable: minor source errors fixed, everything now verifiable

Broad: Covers all potential areas of a relatively minor subject anyway

Neutral: It's an astronomy article...

stable: yes

Illustrated: picture included in template, outside media link in article

ok the rest of this looks good. I'm going ahead and closing this. Sam-2727 (talk) 14:26, 12 August 2019 (UTC)