1. Today! From Earth’s Perspective: Celestial Motion: Stellar Motion Solar Motion Planetary Motion

2. Some stars and constellations Are circumpolar—never rise or set.

3. Constellation vs Asterism!

4. A constellation is one of 88 listed ‘states’ or regions in the sky: like Orion.

5. 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.

6. 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 :

7. Circumpolar Constellations at our Latitude.

8. 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.

9. seasons caused by tilt of earth’s axis, solstices--maximum and minimum light, equinoxes equal light on northern and southern hemisphere.

11. Solar motion: Mean solar day--24 hours by definition. Average return of sun to same angle relative to the horizon.

12. NOTES: Planetary motion: retrograde 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

13. Mars going RETROGRADE: journeying backward against constellations.

14. Venus: always within 46 degrees of the sun— its MAXIMUM ELONGATION (Mercury within 26 degrees)

15. Mercury 8/30/02 Above Cloud Center w/ Venus Upper Left

16. Note conjunction and opposition as seen from the Earth.