The Celestial Sphere

1
The Celestial Sphere
Celestial Equator Ecliptic Two intersecting
planes -- the 4 cardinal pts equinoxes and
solstices
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The sky from 3 different position on Earth
3
Origin of the seasons -- tilt of the Earths
axis
4
Precession
5
Phases of the Moon
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Eclipses of the Sun and Moon
Solar new moon Lunar full moon
Moon must be at one of the nodes of its orbit and
the line nodes points to the Sun
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An Eclipse of the Sun
3 types total, partial, annular
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Eclipse of the Moon
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Next eclipses
Lunar -- total Dec 21, 2010 -- Jun
15, 2011 -- Dec 10, 2011
Solar --. total July 11, 2011 S. Pacific
(Cook Islands, Easter Is. annular
May 20, 2012 W. US
Aug 21, 2017 April 8, 2024 Aug 23, 2044 Aug 12,
2045