202-01-03 The Catholic Church my mother attends has their Christmas Eve midnight mass at 22:00 on 24 Dec.
John ----- Original Message ----- From: "Bill Potts" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Thursday, 2002-01-03 16:19 Subject: [USMA:17173] RE: Celebrations in Maastricht > However, Joe, I'm suggesting constructing such a clock (although, strangely, > at least one person has). > > An example of the use of 24:00 would be the Catholic Church's Christmas > midnight mass. As people who attend it leave their houses on December 24, > it's less confusing to say that it starts at 24:00 on December 24, rather > than at 00:00 on December 25. > > Catholics, of course, know very well the date on which they must set out to > attend midnight mass. However, the same approach would apply to and be > useful for less familiar midnight events. > > Bill Potts, CMS > Roseville, CA > http://metric1.org [SI Navigator] > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On > Behalf Of Joseph B. Reid > Sent: Thursday, January 03, 2002 12:41 > To: U.S. Metric Association > Subject: [USMA:17171] RE: Celebrations in Maastricht > > > Thanks, Bill. I don't recall mentioning 24:00, but I agree with what you > wrote in USMA 17129. However, I would add that 24 lasts for only one > second; 24:00:01 is not valid. Hence it would be very complicated to > construct a clock that would show 24:00 > > >As Joe Reid (I think) has pointed out, it depends on the context. > > > >Although 24-hour clocks don't display 24:00, expressing midnight as 24:00 > is > >explicitly permitted by ISO 8601:1988 as an alternative to 00:00 -- in > >emphasizing the completion of one day, for example, rather than the > >beginning of the next. > > > >I haven't checked ISO 8601:2000, as I don't have a copy. However, Markus > >Kuhn's web site (accessible from http://metric1.org/dateandtime.htm) > >contains the following: > > > >As every day both starts and ends with midnight, the two notations 00:00 > and > >24:00 are available to distinguish the two midnights that can be associated > >with one date. This means that the following two notations refer to exactly > >the same point in time: > > > >1995-02-04 24:00 = 1995-02-05 00:00 > > > >In case an unambiguous representation of time is required, 00:00 is usually > >the preferred notation for midnight and not 24:00. Digital clocks display > >00:00 and not 24:00. > > > >Bill Potts, CMS > > > Joseph B.Reid > 17 Glebe Road West > Toronto M5P 1C8 TEL. 416-486-6071 >
