This is a digital copy of an old drawing. It shows the Sun surrounded by four Earths. There are four Earths, one for each season. Original art by ndreas Cellarius (1596-1665).
Click on image for full size
(c)1995 Visual Language, All Rights Reserved
The Changing Night Sky
If you look at the night sky different times of the year you see
different constellations. This change is due to the motion of the Earth in its
orbit around the Sun. Each day a few stars are visible in the east that were not
visible the night before. If you were to measure how much the sky "shifted" from
one day to the next you would discover that it "shifts" approximately one degree
per day. This should not be surprising because, if you think about it there are
365 days per year and 360 degrees in a circle. Anyway,
the sky doesn't shift, it is another case of
. The "shift" of the sky is really the motion of the earth
around the sun.
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