Talk:MACS J1149 Lensed Star 1

Latest comment: 2 years ago by Zaslav in topic Duration of observability

Created talk-page

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Created the talk-page for the MACS J1149 Lensed Star 1 article - Enjoy! :) Drbogdan (talk) 21:16, 2 April 2018 (UTC)Reply

Distance and "now"

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I think the star is not 9 billion light years away now. Rather, it was when the light reaching us now was emitted. The universe has expanded a lot since then and so its current distance is quite a bit greater. However, I don't know the current distance. — Preceding unsigned comment added by 66.96.194.172 (talk) 02:00, 4 April 2018 (UTC)Reply

  Done Thank you for your comments - yes - agreed - added the following to the lede => (redshift z=1.49; comoving distance of 14.4 billion light-years; lookback time of 9.34 billion years),[1] - should now be ok - please comment if otherwise of course - in any case - Enjoy! :) Drbogdan (talk) 15:16, 4 April 2018 (UTC)Reply

References

  1. ^ Staff (2018). "Cosmological information and results: redshift z=1.49". Wolfram Alpha. Retrieved 4 April 2018.

Magnitude calculations

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I get 2.5121.5 ≈ 4.0, 2.51213.9 ≈ 360,000. WolfmanSF (talk) 03:55, 5 April 2018 (UTC)Reply

All the magnitudes look dubious. The numbers don't occur in the given reference paper. Are they being read from the SED graph? And then calculations performed to get another set of numbers that don't occur in the paper? Lithopsian (talk) 19:59, 5 April 2018 (UTC)Reply

Move title?

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Hi, I noticed that the article name and the full title were not the same, should the page be moved to the more exact MACS J1149+2223 Lensed Star 1 to avoid confusion of the star cluster? User:SuperTurboChampionshipEdition 15:31, 5 April 2018 (UTC) [edit restore/add]Reply

@SuperTurboChampionshipEdition: & others: FWIW - seems the current original article name => "MACS J1149 Lensed Star 1" - may be the much better name choice, based on Search results as follows: "MACS J1149 Lensed Star 1"=> 3,230 Google-Results; 35,600,000 Bing-Results - Compared To - "MACS J1149+2223 Lensed Star 1" => 308 Google-Results; 4,400 Bing-Results - hope this helps in some way - in any case - Enjoy! :) Drbogdan (talk) 17:55, 5 April 2018 (UTC)Reply
Possibly, and possibly not, but pending any move it might be nice if the article title was mentioned, preferably in the lead. In an ideal world, some explanation of why the discoverers call it one thing and Wikipedia calls it something else would also be helpful. Lithopsian (talk) 19:35, 5 April 2018 (UTC)Reply
@Lithopsian: - may or may not be relevant - the current article title was based on the original reference, in Nature (journal), by the discoverers (esp in the abstract => [name of the star was] "(dubbed MACS J1149 Lensed Star 1)")[1] - the terms "MACS J1149+2223 Lensed Star 1" and/or "MACS J1149+2223 Lensed Star-1" do not seem to be mentioned by the discoverers in the original reference.[1] - iac - Enjoy! :) Drbogdan (talk) 19:59, 5 April 2018 (UTC)Reply

  Done - BRIEF Followup re the main article => "restored original title name by the discoverers in the original Nature (journal) reference - please see the talk-page => Talk:MACS J1149 Lensed Star 1#Move title? - and - https://www.nature.com/articles/s41550-018-0430-3 " - hope this helps - iac - Enjoy! :) Drbogdan (talk) 15:27, 6 April 2018 (UTC)Reply

References

  1. ^ a b Kelly, Patrick L.; et al. (2 April 2018). "Extreme magnification of an individual star at redshift 1.5 by a galaxy-cluster lens". Nature Astronomy. 2: 334–342. doi:10.1038/s41550-018-0430-3. Retrieved 5 April 2018.

Brightness ratios and magnitudes need some attention.

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A brightness gain of 2000 equates to a magnitude change of -2.5 X log(10) (2000) =~ -2.5 X 3.3 =~ 8.3 . In the "Characteristics" section, the apparent magnitude increase given with the the "normally" addendum is only about 1.5 . — Preceding unsigned comment added by 58.166.227.224 (talk) 06:11, 7 April 2018 (UTC)Reply

Update yet?

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Fascinating that it was visible in 2016 but not in 2011. Why is this? Has the status of the "star" been checked since? Has it been found since? Misty MH (talk) 09:53, 8 April 2018 (UTC) Misty MH (talk) 09:54, 8 April 2018 (UTC)Reply

Is or was?

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The article states "MACS J1149 Lensed Star 1, also known as Icarus, is a blue supergiant" but this source, used in the article, states "It also no longer exists". Would it therefore not be more correct to state "was a blue supergiant"? The source states that it collapsed into a black hole or wound up as a neutron star. Turismond (talk) 07:28, 9 April 2018 (UTC)Reply

Getting on to dangerous territory. Astronomical observations are almost universally timed at the moment that they are observed. Very deep (ie. distant) events may be timed since the big bang. Populist statements such as this one can only lead to confusion, despite there being a quote direct from the lead researcher. Statements about the simultaneity of specially-separated events in a relativistic universe fall into all sorts of traps; the obvious one is that we just don't know, can't know, what happened until we observe it, but more generally "now" has very specific and not necessarily agreed meanings. Unless you want to launch into extensive semi-philosphical footnotes to such statements, I'd suggest not going there, and even removing the existing statement, referenced or not. Lithopsian (talk) 13:26, 9 April 2018 (UTC)Reply
@Turismond and Lithopsian: Good Question - FWIW (and more simply?) - seems the light from the star we know as "MACS J1149 Lensed Star 1" is currently observed - although the star itself may no longer exist - therefore - "is a blue supergiant" (referring to the observed light) may be ok imo atm - iac - Enjoy! :) Drbogdan (talk) 13:36, 9 April 2018 (UTC)Reply
@Turismond, Lithopsian, and Drbogdan: When talking about astronomical objects that we can currently observe, we always use the present-tense. Example articles include Betelguese, VY Canis Majoris, and UY Scuti—all of which easily might not exist (at least in stellar form) anymore. Another more comparable example would be ULAS J0015+01. The main reason it should be present-tense IMO is that the names "MACS J1149 Lensed Star 1" and "Icarus" refer to the designation we gave to the star. Even if it doesn't technically exist anymore, it's still cataloged. Howpper (talk) 18:01, 9 April 2018 (UTC)Reply
Great question. I would like to add to the confusion by pointing out that according to wikipedia, the one-way speed of light is undefined, meaning that we don't exactly know how long it took the light to arrive here. I hope you are completely confused now! Brian Everlasting (talk) 01:21, 10 April 2018 (UTC)Reply
Thank you for all your answers. It is indeed a rather interesting topic. I guess it is a bit of an astronomical "Missing person" case, where we (roughly) know where the star has once been but probably never find out what became of it. Turismond (talk) 01:39, 10 April 2018 (UTC)Reply

Which galaxy?

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Can one tell which galaxy this star belongs to? S3rvus (talk) 21:14, 29 March 2020 (UTC)Reply

Nope. Kind of the point, it is much too far away to detect anything normally. Lithopsian (talk) 20:06, 30 March 2020 (UTC)Reply

New record?

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New record holder? Article probably needs updating: https://www.nasa.gov/feature/goddard/2022/record-broken-hubble-spots-farthest-star-ever-seen/ wotsuhthedeal (talk) 15:38, 30 March 2022 (UTC)Reply

Duration of observability

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I have not seen anywhere a statement about how long the microlensed brightening has lasted, or will last, or even whether it is still in effect. That appears to be the major constraint on how long we can observe Icarus, so it would be significant information. Zaslav (talk) 21:02, 31 March 2022 (UTC)Reply