Wikipedia:Featured article candidates/IK Pegasi


 * The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was promoted 18:00, 19 June 2007.

IK Pegasi
This otherwise obscure binary star system is of note primarily because it is the nearest known supernova progenitor candidate. But I think the system has other attributes that make it interesting to a person who is interested in astronomy. The article has undergone a peer review and has a good article status. But I'd like to bring it up to FA a rating (although I'm none too interested in front page exposure :). Please let me know what remains to be done so that it is at feature quality and I'll try to address your concerns and expectations. (Yes the lead is only half the maximum allowed length, but I do think it provides a sufficient summary. Unfortunately I do not have a quality photograph of the surrounding star field available.) Thank you. &mdash; RJH (talk) 19:23, 9 June 2007 (UTC)
 * Comment I would like to see an inline citation for every datum in the infobox. This should be the standard for articles on astronomical objects at this point.  If this does not happen by Monday 11 June 2007, I will add "citation needed" tags.  Dr. Submillimeter 19:49, 9 June 2007 (UTC)
 * Reply &mdash; The SIMBAD entry under the "Database references" at the end of the infobox provides the majority of the parameters. I thought that was the purpose of that reference field? For the other values I cited the individual sources. Thanks. &mdash; RJH (talk) 20:20, 9 June 2007 (UTC)
 * Comment - It is unclear that SIMBAD is being used as a reference, and I think the general consensus has been that inline citations are highly preferable to general notes that something was used as a reference.  In this specific article, it is unclear as to which data the SIMBAD database was used for, and the average reader will not be able to figure it out very easily.  If inline citations were used, it would be immediately apparent as to where the data originated from.  Therefore, I would like to see inline citations for every entry in the infobox.  Dr. Submillimeter 01:38, 10 June 2007 (UTC)
 * Reply &mdash; Okay, will do. Thanks. &mdash; RJH (talk) 17:42, 10 June 2007 (UTC)
 * Support I couldn't see anything wrong. Well written, referenced, good layout, sufficient amount of images and so on. Well done. — Wackymacs 07:13, 10 June 2007 (UTC)
 * Support, well-done but is there any reference on IK Pegasi discoverer (or at least any of its components)? Also: "This is the nearest known supernova progenitor candidate". Which one of the components? --Brand спойт 18:37, 10 June 2007 (UTC)
 * Reply &mdash; The Bonn Durchmusterung catalog entry (per the ID=BD +18°4794) was the oldest reference I could find. (Since the star bares a variable star designation of the form introduced by F. W. Argelander, and he also co-produced the BD catalog, I could wildly speculate that it may have been him or one of his co-workers. But I don't have a suitable citation.) The progenitor component is given at the end of the second paragraph in the lead. Otherwise perhaps I am misunderstanding your concern? &mdash; RJH (talk) 18:47, 10 June 2007 (UTC)
 * I've specified, if it's IK Pegasi B :) --Brand спойт 19:13, 10 June 2007 (UTC)
 * It's somewhat redundantly redundant, but thanks. :) &mdash; RJH (talk) 14:31, 11 June 2007 (UTC)
 * Well the second paragraph just says B is a white dwarf. Somebody (like me) who doesn't know much about supernovas wouldn't necessarily know that a white dwarf is more likely to go supernova than a main sequence star eh? Now I know which of the stars is going to go boom. Sheep81 13:09, 18 June 2007 (UTC)
 * The final sentence of the paragraph read, "When the white dwarf approaches the Chandrasekhar limit of 1.44 solar masses, it may explode as a Type Ia supernova." So I was unsure why there was any ambiguity. No matter. :-) &mdash; RJH (talk) 15:11, 19 June 2007 (UTC)


 * Comment. The formulas used in the "Notes" section are too large relative to the text font. Could you use a smaller font size for them? CG 07:45, 12 June 2007 (UTC)
 * Reply &mdash; Unfortunately I've never had much success in setting the font size of the math markup. (C.f. Help:Math.) That's just the way the formulae seem to be displayed. It is rather frustrating not to have better control of the display size. &mdash; RJH (talk) 15:12, 12 June 2007 (UTC)
 * Comment - Why do some infobox entries, such as the U-B colors and B-V colors, have "/-" characters after the numbers? Is this a problem with the templates?  Dr. Submillimeter 21:47, 12 June 2007 (UTC)
 * Reply &mdash; Currently the pair can not be resolved, even by the HST. So, unfortunately, there is no separate color indicies available for the presumably much fainter white dwarf companion. The dash was meant to indicate that no data is available for the B component. Would it be preferable to just show the result as a combined value? Or perhaps it should say "Unknown" instead? Thanks. &mdash; RJH (talk) 22:28, 12 June 2007 (UTC)


 * Comment - I'd have thought the apparent and absolute magnitudes, and distance from us should have been in the lead.


 * However the margin of error for this result is relatively high. - shouldn't that be "large"?

Overall, looks fairly comprehensive but there seem to be alot of commas and bits of clauses about. I need to sleep now but will be back to look later. — Preceding unsigned comment added by Casliber (talk • contribs)


 * Reply &mdash; I've mentioned the distance and visibility in the lead section, and addressed your second issue. The magnitudes are listed in the infobox to the right of the lead. Thanks. &mdash; RJH (talk) 17:56, 15 June 2007 (UTC)


 * Minor oppose - The prose in the "Future evolution" question section switches back and forth between present and future tense with no apparent rhyme or reason. Example from the second paragraph: "Once IK Pegasus A has expanded to the point where its outer envelope overflows the Roche lobe of its companion, a gaseous accretion disk will form around the white dwarf. This gas, composed primarily of hydrogen and helium, then begins to accrete onto the surface of the companion." Can you pick one or the other (preferably future) throughout that section? It doesn't seem to be an issue with the rest of the article (at least I didn't notice). If this is fixed I will support. A couple questions though... what happens to A when B goes supernova? If A and B are so close, won't A engulf B when it turns into a red giant? Didn't B do the same when it became a red giant? And even if we don't all die when the thing explodes, will there be any effects on Earth from a supernova 500 light years away (assuming our own sun hasn't turned into a red giant itself by then)? I dunno if all of these things are necessary to put in the article, but they were questions that arose as I was reading the article which I don't think were ever answered. Maybe if you find a decent source you can stick one or two in? Thanks either way. Nice job! Sheep81 13:09, 18 June 2007 (UTC)
 * Reply &mdash; I attempted to address your concerns about the tense of the last section.
 * The final paragraph answers your question about what happens to A when B explodes. Component A will "lose some mass", possibly create a "gap in the expanding debris", and will retain the (relatively high) velocity it had at the moment of the explosion (of 100-200 km/s).
 * The section on Evolution says what happened when B expanded into a red giant: "...during this time period the two stars shared a common envelope. As a result, the outer atmosphere of the smaller companion (A) may have received an isotope enhancement." Perhaps I need to clarify it further?
 * I can't say for certain that the explosion will occur when the star is 500 light years from Earth. It may be many times more distant when it goes off. The Supernova section covers the topic in some detail. There's also a link in the External links section that covers the topic. The Sun won't turn into a red giant for another 5 Gyr, so it's a long way off.
 * Thank you for the review. &mdash; RJH (talk) 14:55, 18 June 2007 (UTC)
 * Well I was hoping all the verbs that describe what will happen in the future would be changed to future tense (subheading: Future evolution). For instance "accretes" would become "will accrete". But in the interest of time I just went ahead and edited them all (at least I hope I got all of them) myself. You are right, those questions are answered in the text, I just missed them. Thank you for the fine article! Support now. Sheep81 16:12, 18 June 2007 (UTC)
 * Thank you for the corrections. &mdash; RJH (talk) 19:26, 18 June 2007 (UTC)
 * The above discussion is preserved as an archive. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.