Talk:Leap second

message: It seems the IERS doesn't think so: "Leap seconds can be introduced in UTC at the end of the months of December or June, depending on the evolution of UT1-TAI."  — Preceding unsigned comment added by 128.240.225.21 (talk) 11:02, 10 October 2019 (UTC)
replies: text: Yes, up to the present, only the months of June and December have ever been used for leap seconds, and these will always be the preferred months, with second choices being March and September, but the standard allows any month to be used if a catastrophic volcanic eruption or earthquake suddenly changes the length of the day.  The overarching aim is to keep Coordinated Universal Time within nine-tenths of a second of Universal Time.  I haven't mentioned GMT because some sources use it to mean UTC and some to mean UT1. Dbfirs 20:08, 10 October 2019 (UTC)
thread_title:  Can leap seconds really be other months? 

message: Although I have deleted the most blatant OR and opinionising [is that a word?], the sub-section "Questioning the utility of leap seconds" is unsourced and IMO, adds nothing to the article. The sentiments it expresses are given far more succinctly (with citations!) in "International proposals for elimination of leap seconds". It seems to me that it would make a lot more sense to simply delete it and lead the "Future of the leap second" section with the International proposals subsection. As I have already wielded the pruning saw fairly heavily, maybe it is best if I pause for comments? --John Maynard Friedman (talk) 17:24, 27 October 2019 (UTC)
replies: text: I believe I improved this content by removing heading and the first sentence. I am not opposed to further improvement. It seems good to describe problems associated with leap seconds before we get to the proposals to eliminate them. ~Kvng (talk) 14:22, 30 October 2019 (UTC)
replies: text: Yes, that was a big improvement and made the article a lot more readable. I've gone further, deleting some more trivia from that new "sub-lead" so that it really concentrates on stating the essence of the problem and what needs to be done about it. I've moved the International Proposals up to follow that new sub-lead because I believe that most readers want to know what is being done about it before getting into details on the practical issues arising from each time a leap second is created. Looking forward, I know that Wikipedia is not a guide but I do think it would be good to work towards providing an information source that forewarns readers about what they may need to do to get ready. --John Maynard Friedman (talk) 18:37, 30 October 2019 (UTC)
thread_title:  Plan to delete "Questioning the utility of leap seconds" and replace with (by moving up) "International proposals for elimination of leap seconds" 

message: IMO, the lead as it stands at present doesn't meet the standards of WP:LEAD. It doesn't provide a succinct summary of the article and gets bogged down in detail. I have drafted this replacement text. As it is a significant change, I thought I should check first whether anyone disagrees. (Some of the details that I weeded out will need to be relocated, probably at history.
Any objections? --John Maynard Friedman (talk) 21:57, 1 November 2019 (UTC)
replies: text: Thank you both. I really had doubts about keeping the second paragraph but thought perhaps I might be going too far. I am encouraged to be bold and chop it. Since moves to eliminate the leap second (and the problems they have caused) take up a good chunk of the article, a mention in the lead seems essential to me too, especially as it is only two lines. But "modern era" is a bit pompous, I'll change it to "the twenty first century" (I would prefer "recent years" but that would just attract a "how recent" tag!)--John Maynard Friedman (talk) 21:52, 2 November 2019 (UTC)
thread_title:  Proposed new version of the lead 

message: I have replaced the lead as discussed above, with a few minor improvements in the process. I moved the second paragraph of the draft (about the process) down into a new sub-section of that name in the body. The rest of the original lead just duplicated material that was already in the body and better written, so I've discarded it. With great reluctance and fighting my Dr Strangelove impulses, I resisted the temptation to change the title of the History section to A brief history of time. The article is now thrown to the wolves, I rest my case. --John Maynard Friedman (talk) 22:43, 2 November 2019 (UTC)
thread_title: All my proposed changes complete

message: I deleted this edit by   because of WP:COI violation:
Of course someone else is entirely free to reinstate it if they consider it suitable for inclusion. (I'm not saying that it is or that it is not, only that Eric can't be the one to add it.) 𝕁𝕄𝔽 (talk) 15:04, 18 November 2022 (UTC)
replies: text: Notice that I referenced something that was published in New Scientist -- they decided that it was worth publishing, not I. And it's not against the rules to put in a reference to what you have gotten published. I also referenced a letter to New Scientist by someone else. Eric Kvaalen (talk) 10:44, 19 November 2022 (UTC)
replies: text: It's true that citations to published works may be added by the author who is also a Wikipedia editor (unless the motivation seems to be to sell more copies of the publication, which is not the case here). The "Reliable sources" guideline does not specifically mention letters to the editor as being reliable or unreliable, but comments in the talk page archives generally take an unfavorable view of the reliability of such letters. Jc3s5h (talk) 13:06, 19 November 2022 (UTC)
replies: text: WP:RSEDITORIAL does say about letters to the editor: . Vpab15 (talk) 19:33, 19 November 2022 (UTC)

text: My apologies, Eric. I should have checked WP:COI first and Jc3s5h is correct. The relevant policy is WP:SELFCITE. I have reinstated your text and your own NS citation, but not the letter. --𝕁𝕄𝔽 (talk) 21:18, 19 November 2022 (UTC)
replies: text: Turns out that I was right the first time, but for the wrong reason. I failed to spot that both citations were letters. So it has gone again. --𝕁𝕄𝔽 (talk) 23:53, 19 November 2022 (UTC)

text: Of course letters to the editor are not reliable sources for facts. But that's not how I used them. What I said in my edit was that this idea has been suggested, and that fact is proved by the existence of the two letters. I suspect that the idea has been suggested by other people, but I don't have a reference for that. New Scientist is, I think, the most read popular science magazine, so the fact that something has been published by them means that it has had wide exposure. Eric Kvaalen (talk) 04:49, 20 November 2022 (UTC)
replies: text: I don't think published suggestions are noteworthy enough to include in the article unless the suggestion is published in a more prominent way that a letter to the editor. For example, the CGPM resolutions from 2022 include the statement "encourages the BIPM to work with relevant organizations to identify the need for updates in the different services that disseminate the value of the difference (UT1-UTC) and to ensure the correct understanding and use of the new maximum value." That is the sort of suggestion that would be important enough to include in a Wikipedia article. A way that a suggestion made as a letter to the editor could be worthy of inclusion in an article would be if several scholarly sources commented upon the suggestion. Jc3s5h (talk) 17:55, 20 November 2022 (UTC)
thread_title:  Eric Kvaalen proposal: WP:COI vio 

message: The General Conference on Weights and Measures on 18 November 2022 decided to abolish the leap second no later than 2035 (reported by Nature). US law recognizes the CGPM as interpreted by the Secretary of Commerce and Secretary of the Navy as the competent authority to define UTC. But the US is also a member nation of the ITU, and the ITU is responsible for defining how UTC is disseminated. So what steps will we be seeing to actually carry out the CGPM decision?
One step that will be needed will be to alter the way WWV and similar time signals disseminate the difference between UT1 and UTC. Currently this is done by lengthening certain time ticks to indicate the number of deciseconds that should be added to or subtracted from UTC to obtain an estimate of UT1. It is only defined for the range ± 0.9 s.
Options include changing the format of the signal, eliminating that feature of the broadcast altogether, or shutting down WWV and WWVB altogether, as was proposed during a recent budget fight. Jc3s5h (talk) 13:33, 19 November 2022 (UTC)
replies: text: At the risk of drifting into WP:NOTFORUM, I suggest that the message "by 2035 at the latest, could be earlier" is telling the technical committees to produce a plan to make it happen. For WP purposes, we can only wait and see how they resolve it. --𝕁𝕄𝔽 (talk) 13:42, 19 November 2022 (UTC)
replies: text: Trying to avoid WP:NOTFORUM, if we deem the CGPM decision sufficient to assure that the leap second will be abolished, it will change the way we describe leap seconds and UTC in articles. We would have to regard leap seconds as a method of aligning UTC to UT1, used from 1972 until a date to be determined, rather than as a method that will continue indefinitely. And the political reality is that after 2035 UTC might be an offset version of TAI, or might be a variant of Universal Time such that |UTC - UT1| < n, where the value of n has not been decided upon. Jc3s5h (talk) 13:56, 19 November 2022 (UTC)
replies: text: Yet another possibility is that it will not be possible to get all the details worked out by 2035, so leap seconds will continue until they are. John Sauter (talk) 15:39, 19 November 2022 (UTC)
replies: text: It seems that Nature is not convinced that the decision is final either. --𝕁𝕄𝔽 (talk) 11:14, 21 November 2022 (UTC)
thread_title: What next?

message: In the History section, shortly after "rubber second": The phrase "slower than the rate of atomic time by −150 parts per 10 (raised to the tenth)" is confusing.  Is that dash a "minus sign/negative sign"? 
If so: Doesn't slower by a negative amount mean faster?  If "slower" is kept, I suggest removing the negative signs from the various phrases in this section. David10244 (talk) 05:32, 24 January 2023 (UTC)
replies: text: I have changed "slowed" to "offset", using words from the source, to make the meaning clearer. John Sauter (talk) 06:25, 24 January 2023 (UTC)
replies: text: That sounds better, thanks. David10244 (talk) 05:05, 25 January 2023 (UTC)
thread_title:  Slower by a negative amount? 

message: In the Process section, in the phrase "in 1972 the average length of day was approximately 86400.003 seconds and in 2016 it was approximately 86400.001 seconds, indicating an overall increase in Earth's rotation rate over that time period".
It seems like there's a decrease, not an increase, in the rotation rate, since there's a decrease in the "length of day"... if the length of a (rotational) day is measured in "atomic seconds".  But I could be reading this wrong -- not sure. David10244 (talk) 05:44, 24 January 2023 (UTC)
replies: text: I believe you are reading this wrong.  Consider a simpler example: a ball spins at a rate of one rotation every 2 seconds.  In order to make the ball spin at a rate of one rotation every second (decreasing the rotation time) you must increase the rotation rate. John Sauter (talk) 06:29, 24 January 2023 (UTC)
replies: text: Ah, yes, that makes sense.  I was backwards on this one. David10244 (talk) 05:06, 25 January 2023 (UTC)
thread_title:  Length of day 

message: I notice the date format in the article is inconsistent, especially in the references. I found the first edit that introduced dates that contained both the day and the month. It used the dmy format so I have put the  near the top of the article. I will look for inconsistent dates and fix them. Jc3s5h (talk) 16:11, 13 July 2023 (UTC)
thread_title: Article date format