Explanation:
Today is an equinox, a date when day and night are equal.
Tomorrow, and every day until the next
equinox,
the night will be longer than the day in Earth's northern hemisphere,
and the day will be longer than the night in Earth's southern hemisphere.
An equinox
occurs midway between the two
solstices,
when the days and nights are the least equal.
The picture is a composite of hourly images taken of the Sun above
Bursa, Turkey on key days from solstice to
equinox to solstice.
The bottom Sun band was taken during the
winter solstice in 2007 December, when
the Sun could not rise very high in the sky nor stay above the
horizon very long.
This lack of Sun caused
winter.
The top Sun band was taken during the
summer solstice in 2008 June, when the
Sun rose highest in the sky and stayed above the horizon
for more than 12 hours.
This abundance of Sun caused
summer.
The middle band was taken during the
Vernal Equinox in 2008 March, but it is the same sun band that
Earthlings will see today, the day of the
Autumnal Equinox.
Equinox to Equinox:
One Year of APOD in Farsi.
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