NOON

'Noon' is the time halfway through the day ''or'' when the sun is on the meridian. When using solar mean time, it is written as 12:00 in the 24-hour clock and 12:00 noon in the 12-hour clock. 'Midday' is also used as a synonym for noon, although this may also be a more general term to mean ''around'' noon, or very early afternoon.

Contents

Confusion between ''a.m.'' and ''p.m.'' when referring to noon and midnight

Solar noon

Etymology

See also

External link

Confusion between ''a.m.'' and ''p.m.'' when referring to noon and midnight

Main articles: 12-hour clock#Confusion at noon and midnight

Note that the common practice used in most digital clocks, of using 12 p.m. to signify noon (along with 12 a.m
. for midnight) can be confusing. The confusion comes from 12 a.m. seeming to be the next hour in the 10 a.m., 11 a.m. series, but 12.01 p.m. being just after noon. In addition, ''p.m.'' is often associated with night so 12 p.m. may read as midnight.
Etymologically speaking, ''a.m.'' means ''before noon'' (antemeridiem) and ''p.m.'' means ''after noon'' (postmeridiem) and so neither midday nor midnight are correctly referred to using ''a.m.'' or ''p.m.''.

Solar noon

Solar noon is when the sun appears the highest in the sky (nearest zenith), compared to its positions during the rest of the day. It occurs when the Sun is transitting the celestial meridian. This is also the origin of the terms ''ante meridiem'' and ''post meridiem'' as noted above. At solar noon, the sun is approximately due south or due north (the maximum difference between noon and sun due-south is a mere 16 seconds of time at 45 degrees North latitude, and 3 minutes at 85^oN.) The Sun is directly overhead at solar noon at the equator on the equinoxes; at Tropic of Cancer (latitude 23½°N) on the summer solstice in June; and at Tropic of Capricorn (23½°S) on the winter solstice in December. Due to the effects of the use of standard time, daylight saving time, and the equation of time, clock noon and solar noon hardly ever coincide.
The opposite of noon is midnight.

Etymology

The word "noon" is derived from Latin 'nona hora', the ninth hour of the day. As the Roman day started on 6.00 a.m., at sunrise, the first hour would have been from 6.00 till 7.00 a.m and the ninth hour from 2.00 till 3.00 p.m. These hours were important in monasteries, as different prayers were held on them.
The English word "noon" originally applied at 3.00 p.m., but by 1100 AD the meaning had shifted to "midday". (see: [1])

See also

★ Dipleidoscope

External link

★ Generate a solar noon calendar for your location