Greenwich mean time

Home > ... > Science and Technology > Astronomy and Space Exploration > Astronomy: General > ...

Essential reading Compare
side-by-side A Dictionary of Astronomy The Oxford Essential ... The Columbia Encyclopedia, ...

Greenwich mean time

Greenwich mean time or Greenwich meridian time (GMT), the former name for mean solar time at the original site of the Royal Observatory in Greenwich, England, which is located on the prime meridian . In 1925 the numbering system was changed to make GMT equivalent to civil time at the prime meridian, and in 1928 the International Astronomical Union changed the designation of the standard time of the prime meridian to universal time (UT), which is now in general use.

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1E1-GreenwTm" title="Facts and information about Greenwich mean time">Greenwich mean time</a>

Give this article a thumbs-up on StumbleUpon

Cite this article
Pick a style below, and copy the text for your bibliography.

MLA
Chicago
APA

"Greenwich mean time." The Columbia Encyclopedia, Sixth Edition. 2008. Encyclopedia.com. 22 Nov. 2009 <http://www.encyclopedia.com>.

"Greenwich mean time." The Columbia Encyclopedia, Sixth Edition. 2008. Encyclopedia.com. (November 22, 2009). http://www.encyclopedia.com/doc/1E1-GreenwTm.html

"Greenwich mean time." The Columbia Encyclopedia, Sixth Edition. 2008. Retrieved November 22, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-GreenwTm.html

Learn more about citation styles

Greenwich Mean Time

The Oxford Essential Dictionary of the U.S. Military | 2001 | Â© The Oxford Essential Dictionary of the U.S. Military 2001, originally published by Oxford University Press 2001. (Hide copyright information) Copyright

Greenwich Mean Time former term for Universal Time.

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1O63-GreenwichMeanTime" title="Facts and information about Greenwich mean time">Greenwich mean time</a>

Cite this article
Pick a style below, and copy the text for your bibliography.

MLA
Chicago
APA

"Greenwich Mean Time." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 22 Nov. 2009 <http://www.encyclopedia.com>.

"Greenwich Mean Time." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (November 22, 2009). http://www.encyclopedia.com/doc/1O63-GreenwichMeanTime.html

"Greenwich Mean Time." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved November 22, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-GreenwichMeanTime.html

Learn more about citation styles

Greenwich Mean Time

A Dictionary of Astronomy | 1997 | Â© A Dictionary of Astronomy 1997, originally published by Oxford University Press 1997. (Hide copyright information) Copyright

Greenwich Mean Time (GMT) The mean solar time on the Greenwich meridian, now more generally known astronomically as Universal Time (UT). It is the Greenwich hour angle of the mean sun + 12 hours, as the day starts at midnight.

Create a link to this page

Copy and paste this link tag into your Web page or blog:

<a href="http://www.encyclopedia.com/topic/.aspx#1O80-GreenwichMeanTime" title="Facts and information about Greenwich mean time">Greenwich mean time</a>

Cite this article
Pick a style below, and copy the text for your bibliography.

MLA
Chicago
APA

"Greenwich Mean Time." A Dictionary of Astronomy. 1997. Encyclopedia.com. 22 Nov. 2009 <http://www.encyclopedia.com>.

"Greenwich Mean Time." A Dictionary of Astronomy. 1997. Encyclopedia.com. (November 22, 2009). http://www.encyclopedia.com/doc/1O80-GreenwichMeanTime.html

"Greenwich Mean Time." A Dictionary of Astronomy. 1997. Retrieved November 22, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-GreenwichMeanTime.html

Learn more about citation styles

Related entries from encyclopedias, dictionaries and thesauruses

Rate these entries|See all related entries

Free newspaper and magazine articles

	Year 2000 Wire/Greenwich Mean Time-UTA Takes Home 3 Out Of 7 Awards From Breakaway XChange Competition. Business Wire; 9/8/1998
	Greenwich Mean Time-UTA Ranked First in 1999 'Soft Letter 100' Growth Leader Category. Business Wire; 5/12/1999
	Novell Partners With Greenwich Mean Time to Speed Up Year 2000 Problem Resolution. Business Wire; 8/25/1998

Facts and information from other sites

Related articles from newspapers, magazines, and more

	MUSIC; Greenwich time; The 'Pack' is back and Girl Group classics reign Supreme; Greenwich recalls glory days.(Scene) Newspaper article from: The Boston Herald; 4/13/2001; ; 700+ words ; ...life story was used as the means to tie the songs together...coming to the Shubert Theatre, Greenwich's life story has been eliminated...significant as the songs," Greenwich explains, "so he took that...Mary Wilson doing it." So Greenwich's durable songs will continue...about what these songs ...
	New Stores Hit Greenwich, Conn., Business District Just in Time for Holidays. Newspaper article from: Greenwich Time (Greenwich, Connecticut) (via Knight-Ridder/Tribune Business News); 12/3/2003; 700+ words ; ...Holiday shoppers in Greenwich will likely do a...opening just in time for the year's...in the New York Times Style section and...decided to open a Greenwich store after noticing...di Sopra, which means "upstairs" in...see more of the Greenwich Time, or to subscribe...
	Enjoying a mean time in Greenwich; BritishBreak. Newspaper article from: Birmingham Mail (England); 8/26/2009; 700+ words ; ...Royal Observatory are the big Greenwich attractions, but there is so...The Royal Observatory is home to Greenwich Mean Time and the Prime Meridian Line...Planetarium that only opened last year. Greenwich is also perfect for shopaholics...
	A mean time in Greenwich ; PREVIEW Newspaper article from: Evening Standard - London; 6/19/2008; ; 493 words ; ...public spaces of Woolwich, Greenwich and Docklands. If this is...aerial replays.. Several of Greenwich's historic sites also host...fourmetre swaying poles; in Greenwich Park, the area outside the...Until Sunday. For details and times of events: 020 8305 1818 or...
	Greenwich mean time explained Newspaper article from: Express & Echo (Exeter UK); 10/25/2008; 329 words ; British Summer Time is the daylight...effect in the UK. Greenwich Mean Time stays the...measured from the Greenwich Meridian Line at...Observatory in Greenwich, London. It is...permanently. This means that the clocks...
	Beeb's mean time over Greenwich; Sports Agenda.(Sport) Newspaper article from: The Daily Mail (London, England); 4/23/2009; 504 words ; ...2012 equestrian events taking place in Greenwich Park -- fast becoming the Games' most controversial venue. Protest group No to Greenwich Olympics Equestrian Events (NOGOE...Liz Coyle, chairman of the Friends of Greenwich Park, who was interviewed by Warner...
	The nick of time ... Greenwich line plaques stolen ; LOCAL LONDON Newspaper article from: Evening Standard - London; 6/20/2008; 322 words ; ...Brass plaques marking the prime meridian through Greenwich have been stolen, believed to be for scrap metal...south line used as the reference point to measure Greenwich Mean Time. Lewisham councillor Andrew Milton described the...
	It's about time for a change to our clocks After the changing of the clocks at the weekend, a debate has continued to rage about whether we should stick with Greenwich Mean Time and British Summer Time or be one hour ahead of current arrangements all year round. Angela Wright, managing director of Crealy Great Adventure Parks, explains why she supports adopting Double British Summer Time Newspaper article from: Express & Echo (Exeter UK); 10/30/2007; 700+ words ; ...continued to rage about whether we should stick with Greenwich Mean Time and British Summer Time or be one hour ahead of current arrangements all...why she supports adopting Double British Summer Time How often do you hear people say 'if only there...
	Obama the orator delights the crowd ; Esterday, in the early morning Greenwich Mean Time, Barack Obama made some big promises in his speech accepting to run for the Democratic presidential candidate for 2008. Addressing a packed Invesco stadium, a mile above sea level in Denver, Colorado, he invoked past heroes, outlined a plan for the future, strummed our heartstrings and spoke a lot of good sense. Newspaper article from: Western Morning News, The Plymouth (UK); 8/30/2008; 700+ words ; Esterday, in the early morning Greenwich Mean Time, Barack Obama made some big promises in his speech accepting to run for the Democratic presidential candidate for 2008. Addressing...
	ONE thing visitors to South Africa have to get used to is the phenomenon known as 'Africa Time.' This is not like Greenwich mean time and has nothing whatsoever to do with readjusting your watch, but rather refers to the pace at which life is carried out. Newspaper article from: Irish Independent (Dublin, Republic of Ireland); 6/8/2009; 427 words ; ...africa style ONE thing visitors to South Africa have to get used to is the phenomenon known as 'Africa Time.' This is not like Greenwich mean time and has nothing whatsoever to do with readjusting your watch, but rather refers to the pace at which...