Length of Day


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Length of Day

 

the interval of time between sunrise and sunset, during which the sun is above the horizon. The length of day depends upon the geographic latitude of a place and upon the inclination of the sun. At the equator, the length of day is constant and equals 12 hours. In the northern hemisphere, the length of day is more than 12 hours during the positive inclination of the sun (that is, in the spring and summer) and less than 12 hours during the negative inclination of the sun (in the autumn and winter). At the equinoxes (spring and autumn), the day equals the night (if one does not consider refraction) everywhere on the earth. The longest day is the summer solstice and the shortest is the winter solstice. Within the polar circles, the length of day in the summer can exceed 24 hours (the polar day), and at the poles daytime lasts six months.

References in periodicals archive ?
Relying on the law of spin isochronism Alfv6n and Arrhenius (1976 [10]) infer for the primitive Earth a length of day of 6 hours (p.
Using the flow patterns determined by other researchersfrom changes in the magnetic field (which is generated by core flow), Speith's group indeed found that the topography of the core-mantle boundary could be affecting the length of day.
Between them stretch a length of days that are to be counted--'ordinary' in fact comes from 'ordinal' and is not meant to suggest that the time is ordinary or simply commonplace, a gray area we pass through between the high sacred holidays of Easter and Christmas.
In terms of length of days, however, driving duties here can be longer than the 10-hour region because of a four-day working week.
And so through all the length of days your goodness fails me never; Good Shepherd, may I sing your praise within your house forever
They all deal with different realms, but they come with the same very large promise attached: do them "in order that you may fare well and have length of days.
The explanation of its effect on the length of days lies in the spin of the Earth and its atmosphere.
It is the time when the length of days and nights are almost equal, hence explaining that fact that "equinox" derives from the Latin word meaning "equal night.
Popes come and go, some for short stays, others for length of days.
You will come to appreciate the cycle of the seasons, the changing length of days and the vagaries of weather.
Had this imaginative momentary pope been given length of days, it would have been interesting to see the character and caliber of bishops and cardinals he would have named.