Title: Today!
1Today! From Earths Perspective
Celestial Motion Stellar Motion
Solar Motion Planetary Motion
2Some stars and constellations Are
circumpolarnever rise or set.
Celestial Motion
3Constellation vs Asterism!
4A constellation is one of 88 listed states or
regions in the sky like Orion.
5An 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.
6Once you find the North Star, Turn around 180
degrees The Ecliptic and the planets will be in
the sky toward the South.
Finding Planets
7Circumpolar Constellations at our Latitude.
8The 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.
9seasons caused by tilt of earths axis,
solstices--maximum and minimum light,
equinoxes equal light on northern and southern
hemisphere.
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11Solar motion Mean solar day--24 hours by
definition. Average return of sun to same angle
relative to the horizon.
12NOTES 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
13Mars going RETROGRADE journeying backward
against constellations.
14Venus always within 46 degrees of the sun its
MAXIMUM ELONGATION (Mercury within 26 degrees)
15Mercury 8/30/02Above Cloud Centerw/ Venus Upper
Left
16Note conjunction and opposition as seen from the
Earth.