1. Mr. Ahearn Earth Science 2010
Earth In Space
Mr. Ahearn
Earth Science
2010

2. Motions of Celestial Objects
Celestial Sphere- Imaginary sphere encircling Earth on which all objects in night sky appear.

3. Motions of Celestial Objects
Celestial objects appear to move circular or curved paths (east-west 15*/hr)
Sun, moon, planet, stars

4. Star Paths Stars overhead @ equator follow same path as sun.
Stars in southern hemisphere may only be visible briefly (below celestial equator)
Northern hemisphere move in circles around Polaris (15*/hr.)

5. Path of Planets Word planet means “wanderer”
Move 15*/hr. plus each has own characteristic motion.
Retrograde motion

6. Path of Planets

7. Constellations
Apparent patterns people use to mark star positions

8. Models of the Night Sky Geocentric: Earth-centered
Heliocentric: Sun-centered

9. Evidence for Heliocentric
Foucault Pendulum
Coriolis Effect

10. Complete Review Book Questions #1-16

11. Apparent Motions Of The Sun
Time is based off of sun’s motion

12. Seasons Northern Hemisphere
-sun highest in sky June 21 (summer solstice)
-sun lowest in sky December 21 (winter solstice)
- Sept.22 (vernal equinox)
-March 21(vernal equinox)

15. Latitude and Angle of the Sun
Path of sun depends on your position
Sun is never directly over head in the Continental USA
Can be directly overhead in the tropics (23.5 N to 23.5 S)
Arctic and Antarctic first day of summer sun never sets, first day of winter sun never rises

17. Hours of Daylight At equinoxes daylight last 12hrs (except @ poles.
At equator 12 hrs of day and nights yr. round

18. Summer Solstice
Winter Solstice

19. Equinox

21. Answer Questions #17-45 Review Book p.260

22. The End See you in outer space!