Explanation:
If you took a picture of the Sun at the same time each day,
would it remain in the same position?
The answer is no, and the shape traced out by the
Sun over the course of a year is called an
analemma.
The Sun's apparent shift is caused by the
Earth's motion around the Sun when combined with the
tilt of the Earth's rotation axis.
The Sun will appear at its highest point of the
analemma during
summer and at its lowest during
winter.
Today, the Winter Solstice day in Earth's northern hemisphere,
the Sun is at the bottom of the analemma.
Analemmas
created from different
latitudes
would appear at least slightly different, as well as
analemmas
created at a different time each day.
This particular analemma was built up by 46 separate
Sun photographs taken during 2003 in
Athens,
Greece.
Pictured in the foreground of
this composite image are pillars called the
Porch of Maidens, part of the ancient
Erechtheum
which was completed in 407 BC.
Note : APOD Editor to Speak in New York on Jan. 2
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