I. The Sky

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I. The Sky II. The Sky Its Motion III.
Annual cycle of the Sun A. The ecliptic
projection of Earths orbit on the sky.
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III. Annual cycle of the Sun A. The ecliptic
projection of Earths orbit on the sky.
1. In Jan, Sun appears in Sagittarius in
March, Aquarius this led to Astrology 2.
the sun, moon planets travel along the Zodiac,
an 18o band centered on the
ecliptic 3. the earth circles the sun in
365.25 days B. Seasons 1. It is not due
to the earth being closer to the sun! The
earths orbit is nearly a circle. 2. It
is due to earths axis being tilted 23.5o
3. The tilt causes changes in the amount of
solar energy that hits the earths
surface. a. Summer Solstice sun is high, rays
are direct b. Spring/Fall Equinox equal
hours of sun/dark c. Winter Solstice sun
is low, rays are indirect
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