Full Moon Cycle and The Year
Formulated in another way: the full moon cycle is the period that it takes the Sun to return to the perigee of the Moon's orbit (as seen from the Earth). So it is a kind of "perigee year", similar to the eclipse year which is the time for the Sun to return to the ascending node of the Moon's orbit on the ecliptic.
Why does a full moon cycle last almost 14 lunations rather than just the 12.37 lunations of a year? This would be the case, if the moon's orbit kept a constant orientation with respect to the stars, but the tidal effect of the Sun causes the orbit to precess over a cycle just under 9 years. In that time, the number of full moon cycles passed becomes one less than the number of sidereal years passed.
Hence the full moon cycle can be defined such that the lunar precession cycle is the beat period of the full moon cycle and sidereal year. See lunar precession.
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Famous quotes containing the words full, moon, cycle and/or year:
“When cups went round at close of day
Is not that how good stories run?
The gods were sitting at the board
In their great house at Slievenamon.
They sang a drowsy song, or snored,
For all were full of wine and meat.”
—William Butler Yeats (1865–1939)
“For now the moon with friendless light carouses
On hill and housetop, street and marketplace,
Men will plunge, mile after mile of men,
To crush this lucent madness of the face....”
—Allen Tate (1899–1979)
“The cycle of the machine is now coming to an end. Man has learned much in the hard discipline and the shrewd, unflinching grasp of practical possibilities that the machine has provided in the last three centuries: but we can no more continue to live in the world of the machine than we could live successfully on the barren surface of the moon.”
—Lewis Mumford (1895–1990)
“But I must needs take my petulance, contrasting it with my accustomed morning hopefulness, as a sign of the ageing of appetite, of a decay in the very capacity of enjoyment. We need some imaginative stimulus, some not impossible ideal which may shape vague hope, and transform it into effective desire, to carry us year after year, without disgust, through the routine- work which is so large a part of life.”
—Walter Pater (1839–1894)