Astronomy Picture of the Day

Movie: Analemma Over New Jersey


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#104887 by @ 05.12.2007 00:00 - nach oben -
Movie: Analemma Over New Jersey


Explanation:

An analemma
is that figure-8 curve that you get when
you mark
the position
of the Sun at the same time
each day throughout planet
Earth's
year.

Above,
26 separate exposures
were recorded to illustrate
the regular solar motion -- a difficult
project performed mostly during the calendar year 2006.

The images were taken at 8 am in the morning in northern
New Jersey,
USA,
and digitally combined with a single foreground image later.

The individual images have since been combined into
a movie.

Solstices
correspond to the top and bottom of the figure-8, indicating the
northern and southernmost excursions of the Sun in the sky.

The tilt of planet
Earth's axis

and the variation in speed as it moves around its orbit combine to
produce the graceful
analemma curve.




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