ANO
(AWN-yoh)
Spanish
for year Common
clues: Spanish
year; Year abroad; Year in Yucatan; 12 meses; Calendario span;
Mayo to mayo; Doce meses; Enero starts it; Year in
Uruguay Crossword
puzzle frequency:
3 times a year Frequency
in English language:
56343 / 86800 Video: Earth:
Year 3000
A
year (from Old English gēr) is the time between two
recurrences of an event related to the orbit of the Earth around
the Sun. By extension, this can be applied to any planet: for
example, a "Martian year" is the time in which Mars
completes its own orbit.
A
calendar year is the time between two dates with the same name in
a calendar. Solar calendars usually attempt to predict the four
seasons, but because the length of individual seasonal years
varies significantly, they instead use an astronomical year as a
surrogate. For example, the ancient Egyptians used the heliacal
rising of Sirius to predict the flooding of the Nile.
The
Gregorian calendar attempts to keep the vernal equinox on or
close to March 21; hence it follows the vernal equinox year. The
average length of its year is 365.2425 days.
Among
solar calendars in wide use today, the Persian calendar is one of
the most precise. Rather than being based on numerical rules, the
Persian year begins on the day (for the time zone of Tehran) on
which the vernal equinox actually falls, as determined by precise
astronomical computations.
No
astronomical year has an integer number of days or lunar months,
so any calendar that follows an astronomical year must have a
system of intercalation such as leap years.
In
the Julian calendar, the average length of a year was 365.25
days. (This is still used as a convenient time unit in astronomy
as shown below.) In a non-leap year, there are 365 days, in a
leap year there are 366 days. A leap year occurs every 4 years.
This
article is licensed under the GNU
Free Documentation License.
It uses material from the Wikipedia
article "Year".
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