This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects:

Time Low‑importance This article is within the scope of WikiProject Time, a collaborative effort to improve the coverage of Time on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.TimeWikipedia:WikiProject TimeTemplate:WikiProject TimeTime Low This article has been rated as Low-importance on the project's importance scale.

could we add that it is sometimes written with the greek symbol μ mu ? Olivier --134.130.140.116 11:22, 3 March 2006 (UTC)[reply]

There is a move discussion in progress on Talk:1 E-18 s which affects this page. Please participate on that page and not in this talk page section. Thank you. —RFC bot 21:49, 4 September 2009 (UTC)[reply]

I removed this uncited dubious entry, because it made no sense ("a fifth"... of what?)

• 4.63 microseconds – a fifth (a 60th of a 60th of a 60th of a second)

feel free to work out what it was supposed to mean, and put it back fixed.

I also removed this;

• 277.8 microseconds – a fourth (a 60th of a 60th of a second), used in astronomical calculations by al-Biruni and Roger Bacon in 1000 and 1267 AD, respectively.^[1][2]

which is also nonsense, and the references did not appear to support it either ("fourth" (and, for that matter, "fifth") were not used in the context of seconds, and every time they were used, it was hyphenated, like "fourth-part", in the context of an actual sentence explaining what it was a part of.

In reply to User:120.151.160.158 who removed the bits about "fourth" and "fifth" -- I am pretty sure it means 277.8 μs is the result of dividing an hour by 60, four times, or 277.8 = 1 hour / (60 ^ 4). Likewise 4.63 μs = 1 hour / (60 ^ 5). From looking at the Google Books version of the al-Biruni book, I also realized that this follows a logical progression from "seconds" and also explains why one abbreviation for seconds is two little apostrophes. If you will, hour = zeroth. Minute = first. Second = second. 16.667 ms = third. 277.8 μs = fourth. 4.63 μs = fifth. Furthermore, Sexagesimal says 'Until at least the 18th century, 1/60 of a second was called a "tierce" or "third".' Some references are given. I believe that 1 μs is something like 12 sixths, 57 sevenths, 36 eighths.

Despite figuring this out, I'm not sure how to work this back in to the article. --Officiallyover (talk) 17:05, 2 September 2015 (UTC)[reply]

probably should be defined better on the Second#Based_on_subdivisions_of_the_moon_cycle article and linked to that Alanbelllibertus (talk) 15:03, 23 January 2017 (UTC)[reply]