Today!

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Today! From Earths Perspective
Celestial Motion Stellar Motion
Solar Motion Planetary Motion
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Some stars and constellations Are
circumpolarnever rise or set.
Celestial Motion
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Constellation vs Asterism!
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A constellation is one of 88 listed states or
regions in the sky like Orion.
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An asterism is not on the list Of 88, but forms a
shape In the sky like the Big Dipper, Part of
the constellation Ursa Major.
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Once you find the North Star, Turn around 180
degrees The Ecliptic and the planets will be in
the sky toward the South.
Finding Planets
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Circumpolar Constellations at our Latitude.
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The stars (at a given time of night) shift 1
degree a day Because the earth is orbiting the
sun.
Thus the sidereal day is 23 hours and 56
minutes It is the time for a star to return to
the same place In the sky.
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seasons caused by tilt of earths axis,
solstices--maximum and minimum light,
equinoxes equal light on northern and southern
hemisphere.
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Solar motion Mean solar day--24 hours by
definition. Average return of sun to same angle
relative to the horizon.
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NOTES Planetary motion retrograde
motion--apparent backtracking of planets in sky
from earth's perspective. inner
planets--Me and Ve --stay within
'maximum elongation'. conjunction
vs opposition
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Mars going RETROGRADE journeying backward
against constellations.
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Venus always within 46 degrees of the sun its
MAXIMUM ELONGATION (Mercury within 26 degrees)
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Mercury 8/30/02Above Cloud Centerw/ Venus Upper
Left
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Note conjunction and opposition as seen from the
Earth.