1.) Today is the vernal equinox (the first day of spring). (Someday I will understand/remember what an equinox is.) The equinox is when the elliptic (the apparent path of the sun) crosses the celestial equator (the earth's equator extended up to the sky). Days with an equinox have nearly an equal length for both night and day; however, this is not entirely accurate because commonly the day is defined as the period that sunlight reaches the ground in the absence of local obstacles. From Earth, the Sun appears as a disc and not a single point of light; so, when the centre of the Sun is below the horizon, the upper edge is visible. Furthermore, the atmosphere refracts light; so, even when the upper limb of the Sun is below the horizon, its rays reach over the horizon to the ground. ... These effects together make the day about 14 minutes longer than the night at the equator, and longer still at sites toward the poles.
from http://en.wikipedia.org/wiki/Equinox
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