As the earth rotates, the sun appears to sweep across the sky from east to west, and the path it follows changes from season to season. In the northern hemisphere the sun rises at its most southerly point in midwinter - this is known as the winter solstice (December 21st) - and in mid-summer at its most northerly - the summer solstice (June 21st). Midway between those dates the sun rises due east and sets due west on the spring equinox (March 21st) and the autumn equinox (September 23rd). On those dates the sun rises at 6 a.m. and sets at 6 p.m. all over the world - the word "equinox" is from the Latin meaning "equal night".
"That will be 7 a.m. and 7 p.m. where I live! " ed.
