Noon

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For other uses, see Noon (disambiguation).
"Midday" redirects here. For other uses, see Midday (disambiguation).
"Noon time" redirects here. For the song by Zion I, see Heroes in the City of Dope.
"True Noon" redirects here. For the 2009 film, see True Noon (film).

Noon (also midday or noon time) is usually defined as 12 o'clock in the daytime. The term midday is also used colloquially to refer to a range of time, often 11 a.m. to 1 p.m. Solar noon is 12 o'clock apparent solar time, or around 12 – 1 p.m. local time, depending on daylight saving time and the moment when the sun crosses the meridian. Solar noon is when the sun is at its highest elevation in the sky. The clock time of solar noon depends on the longitude and date.[1]

The opposite of noon is midnight.

In many cultures in the Northern Hemisphere, noon had ancient geographic associations with the direction "south" (as did midnight with "north" in some cultures). Remnants of the noon = south association are preserved in the words for noon in French (Midi) and Italian (Mezzogiorno), both of which also refer to the southern parts of the respective countries. Modern Polish, Ukrainian, and Serbian go a step farther, with the words for noon (południe, південь, пoднe – literally "half-day") also meaning "south" and the words for "midnight" (północ, північ, пoнoħ – literally "half-night", as with English mid(dle) meaning "half") also meaning "north".

Etymology[edit]

A clock tower showing 12 o'clock noon

The word noon is derived from Latin nona hora, the ninth hour of the day, and is related to the liturgical term none. The Roman and Western European medieval monastic day began at 6:00 a.m. (06:00) at the equinox by modern timekeeping, so the ninth hour started at what is now 3:00 p.m. (15:00) at the equinox. In English, the meaning of the word shifted to midday and the time gradually moved back to 12:00 local time (that is, not taking into account the modern invention of time zones). The change began in the 12th century and was fixed by the 14th century.[2]

Solar noon[edit]

Solar noon is the moment when the sun transits the celestial meridian – roughly the time when it is highest above the horizon on that day ("Sun transit time"). This is also the origin of the terms ante meridiem (a.m.) and post meridiem (p.m.) as noted below. The sun is directly overhead at solar noon at the Equator on the equinoxes, at the Tropic of Cancer (latitude 23° 26′ 16″ N) on the June solstice, and at the Tropic of Capricorn (23° 26′ 16″ S) on the December solstice. In the Northern hemisphere the sun is directly to the south of the observer at solar noon, and in the Southern hemisphere it is directly to the north.

Nomenclature[edit]

Noon is commonly indicated by 12 p.m., and midnight by 12 a.m. While some argue that such usage is "improper"[3] based on the original Latin meanings (a.m. stood for ante meridiem and p.m. for post meridiam, meaning "before the meridian" and "after the meridian" respectively), the usage of 12 p.m. to refer to noon is conventional. An earlier standard of indicating noon as "12M" or "12m" (for "meridies"), which was at one time specified in the U.S. GPO Government Style Manual, has fallen into relative obscurity; the current edition of the GPO makes no mention of it.[4][5][nb 1]

However, some still consider the use of 12 a.m. and 12 p.m. confusing and seek a less ambiguous phrasing. Common alternative methods of representing these times are:

  • to use a 24-hour clock (00:00 and 12:00, 24:00; but never 24:01)
  • to use "12 noon" or "12 midnight" (though "12 midnight" may still present ambiguity regarding the specific date)
  • to specify midnight as between two successive days or dates (midnight Saturday/Sunday or midnight December 14/15)
  • to use "12:01 a.m." or "11:59 p.m." This final usage is common in the travel industry, especially train and plane schedules, to avoid confusion as to passengers' schedules

See also[edit]

Notes[edit]

  1. ^ The 29th edition of the U.S. GPO Government Printing Office Style Manual (2000) section 12.9

References[edit]

External links[edit]

Shamsi Day Gregory Day «Noon» Shamsi Day Gregory Day «Noon» Shamsi Day Gregory Day «Noon»
1 Farvardin 21 March 12:07 7 Shahrivar 29 August 12:01 20 Azar 11 December 11:53
5 Farvardin 25 March 12:06 10 Shahrivar 1 September 12:00 22 Azar 13 December 11:54
8 Farvardin 28 March 12:05 13 Shahrivar 4 September 11:59 24 Azar 15 December 11:55
12 Farvardin 1 April 12:04 16 Shahrivar 7 September 11:58 26 Azar 17 December 11:56
15 Farvardin 4 April 12:03 19 Shahrivar 10 September 11:57 28 Azar 19 December 11:57
19 Farvardin 8 April 12:02 22 Shahrivar 13 September 11:56 30 Azar 21 December 11:58
22 Farvardin 11 April 12:01 25 Shahrivar 16 September 11:55 2 Dey 23 December 11:59
26 Farvardin 15 April 12:00 28 Shahrivar 19 September 11:54 4 Dey 25 December 12:00
31 Farvardin 20 April 11:59 30 Shahrivar 21 September 11:53 6 Dey 27 December 12:01
5 Ordibehesht 25 April 11:58 2 Mehr 24 September 11:52 8 Dey 29 December 12:02
12 Ordibehesht 2 May 11:57 5 Mehr 27 September 11:51 10 Dey 31 December 12:03
24 Ordibehesht 14 May 11:56 8 Mehr 30 September 11:50 12 Dey 2 January 12:04
5 Khordad 26 May 11:57 11 Mehr 3 October 11:49 14 Dey 4 January 12:05
13 Khordad 3 June 11:58 15 Mehr 7 October 11:48 17 Dey 7 January 12:06
18 Khordad 8 June 11:59 18 Mehr 10 October 11:47 19 Dey 9 January 12:07
23 Khordad 13 June 12:00 22 Mehr 14 October 11:46 22 Dey 12 January 12:08
28 Khordad 18 June 12:01 27 Mehr 19 October 11:45 24 Dey 14 January 12:09
1 Tir 22 June 12:02 4 Aban 26 October 11:44 27 Dey 17 January 12:10
6 Tir 27 June 12:03 12 Aban 3 November 11:43 30 Dey 20 January 12:11
11 Tir 2 July 12:04 20 Aban 11 November 11:44 4 Bahman 24 January 12:12
17 Tir 8 July 12:05 26 Aban 17 November 11:45 9 Bahman 29 January 12:13
25 Tir 16 July 12:06 1 Azar 22 November 11:46 22 Bahman 11 February 12:14
4 Mordad 26 July 12:07 4 Azar 25 November 11:47 7 Esfand 26 February 12:13
14 Mordad 5 August 12:06 7 Azar 28 November 11:48 12 Esfand 3 March 12:12
21 Mordad 12 August 12:05 10 Azar 1 December 11:49 17 Esfand 8 March 12:11
26 Mordad ا17 August 12:04 13 Azar 4 December 11:50 21 Esfand 12 March 12:10
31 Mordad 22 August 12:03 15 Azar 6 December 11:51 24 Esfand 18 March 12:09
3 Shahrivar 25 August 12:02 17 Azar 8 December 11:52 28 Esfand 19 March 12:08