Talk:Greenwich Mean Time
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[edit] UTC
I'd like to know when the UTC took over from GMT because I have never seen UTC before coming to this site, hower GMT is still widly used all over The Net and in Newspapers and Television.
- I don't know. I believe that these days civil time in the UK is UTC and in summer UTC+1, and we call them GMT and BST. Certainly the pips are synched to UTC. Morwen - Talk 19:27, 22 Jun 2004 (UTC)
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- Within the UK (and, I presume, UK-registered/based shipping?) GMT and BST are the only names used for time as measured in the UK. People outside the UK however, not wanting to appear UK-centric, seem to utilise the alternative expression of 'UTC'. They are, for most practical purposes, the same (I believe the leap-seconds and other adjustments may not always be exactly equivalent, but for most practical purposes they are). --VampWillow 22:54, 22 Jun 2004 (UTC)
What in the UK should you use to denote that the time you are specifying is local in the sense that something occurs at 10AM - 10AM GMT in the winter and 10AM BST in the summer? Clearly if I specify just 10AM then it could be just about any time. If I say 10AM GMT then this will be the wrong time all summer. --KayEss 06:04, 14 Sep 2004 (UTC)
[edit] UT1
UT1 is the same as GMT, isn't it? Currently UT1 redirects to Universal Time. —Ashley Y 13:40, 2005 Jan 24 (UTC)
- Universal Time was invented as another name for GMT in 1928. UT was split into UT0, UT1, and UT2 in the 1960s. UTC was invented in 1972. But GMT has a much longer history than that. It began when the Royal Observatory was founded at Greenwich in 1675. For astronomers 00:00 GMT meant noon, but for civilians 00:00 GMT meant midnight, twelve hours earlier. As of 1 January 1925, the astronomical GMT day was shifted by twelve hours so that it also began at midnight. Thus GMT has not always been the same as UT1 by any stretch of the imagination. But UT1 has always been a type of Universal Time, thus the redirect is correct. — Joe Kress 08:02, Jan 25, 2005 (UTC)
[edit] Dublin-Mean Time
Could Dublin-Mean Time be included in this section or on a seperate page.It was 25 minutes behind of Greenwich according to The Irish Times Book Of The Century.I can't find my copy of the book but anyone with a copy could add the page if it is considered notable.--Fenian Swine 22:59, 22 August 2005 (UTC)
- Hmm lots of cities had local times. Why add Dublin in particlular? Theresa Knott (a tenth stroke) 11:56, 25 August 2005 (UTC)
- Is that apart from the fact that Dublin is the greatest city in the World.I was unaware of other local times.Why not add a page with the other local times.--Muc Fíníneach 15:01, 25 August 2005 (UTC)
- You are free to create a page entitled "Dublin mean time" if you can make it larger than a stub (stubs serve no useful purpose). See Washington mean time and Washington meridian. — Joe Kress 17:08, August 25, 2005 (UTC)
[edit] The M means Mean?
I always thought it was Greenwich Meridian Time.
- Everything I've read has GMT meaning Greenwich Mean Time, but some authors may have used GMT to mean Greenwich Meridian Time, which means almost the same thing. "Mean" indicates that the equation of time has been applied to the solar time at the Greenwich meridian. — Joe Kress 22:35, September 1, 2005 (UTC)
[edit] Zulu
The article stated:
In the military, GMT is often referred to as "Zulu" time, ie 2000 Zulu would be 8:00pm in Greenwich.
I have removed this. First of all, Zulu is another name for UTC, not GMT. Second of all, even if it were identical to GMT, then 2000 Zulu would 8:00pm in Greenwich only during winter, not during summer. --Netvor » user | talk | mail | work » 13:25, 15 March 2006 (UTC)
[edit] Colored map slightly unclear
It is currently captioned: Dark colours indicate countries observing daylight saving. It's not clear which colors are dark. Are Russia and Eastern Europe "dark"? --Ds13 00:01, 5 May 2006 (UTC)
[edit] 211's addition
211, you previously agreed at Talk:Greenwich Mean Time/Time Cube not to re-add this material. This behavior is inappropriate. You may not add any such material without first convincing the other editors on the talk page. — Knowledge Seeker দ 08:14, 30 September 2006 (UTC)
[edit] Merging?
Why don't we merge UTC, UT1 and GMT together in to 1 article named maybe, International Time, etc. --Jacklau96 01:11, 19 November 2006 (UTC)
- Because they are different things? GMT has had a longer history than e.g. UTC. Also UTC strictly is not the same as GMT. In any case, International Time (without a qualifier such as "Atomic") is a non-existent: we have Universal Time instead. Tom Peters 14:11, 19 November 2006 (UTC)
[edit] Does anyone still use real GMT?
UTC is the international standard and it seems that even the broadcast time signal in the UK is UTC. The article does not make it clear whether there is someone still keeping a clock set at real GMT and whether anyone uses it and why. OK now re-read. GMT and everyone's time zones based on UT1 and there is a shift every so often by leap seconds to UTC & UT in step. JMcC 19:03, 27 November 2006 (UTC)
ZULU = GMT = UTC Greenwich Mean Time = Co-ordinated Universal Time (UTC) = "ZULU" a short form for the aforementioned. Originally referred to by all radio operators as Greenwich Mean Time or GMT... the term was "universalized" in the 70/80's to UTC, Co-ordinated Univeral Time. The term "ZULU" is the equivilant of the aforementioned, when referring to GMT or UTC.. i.e. "1436 ZULU" would be 14:36 UTC or 14:36 GMT; the purpose of which was and is simply to have a single, universal time standard by which people may set schedules worldwide... i.e. to someone in North America, 1436 ZULU is the same as to someone in Africa, or anywhere else in the world. Makes setting schedules amongst, for example, radio amateurs (shortware radio operators) easier. See WWV, WWVH time standards.
