August 26 – 10am Class

1. Turn in HW 1 if you didn’t turn it in on Wednesday • On line quiz #1: • Go to d2l and click on “Quizzes” • Open book, notes, anything, but do not talk to • other students • No time limit • Unlimited number of attempts • Graded automatically on d2l • Will start Saturday morning at 8am • Finish before the beginning of class next Friday • Key will be posted after class next Friday. August 26 – 10am Class

2. Lascaux Cave Paintings: Cro-Magnons recorded the lunar cycle 15,000 years ago http://news.bbc.co.uk/2/hi/science/nature/975360.stm

3. PATTERNS IN THE SKY • Ancient peoples observed the Sun and stars and created calendars that marked the yearly passage of time • Earth rotates on its axis once every 24 hours • Earth revolves around the Sun once every 365 days • The stars appear to rise in the east and set in the west every night, on a big dome called the celestial sphere.

4. Celestial Sphere and Constellations The sky is divided into 88 "official" constellations, although in reality the stars in any particular constellation are at different distances from Earth.

5. Ancient Egyptian celestial sphere:the goddess Nut (“noot”) c. 3000 BC Nut gave birth to the Sun god “RA” every morning

6. Hebrew Cosmology And God said, “Let there be a vault in the midst of the waters, and let it divide water from water.” And God made the vault and it divided the water beneath the vault from the water above the vault, and so it was. - Genesis 1:6 Michaelangelo’s depiction of the creation Of the planets and stars

7. God had divided the waters "above" from the waters "below" by constructing an immense dome that held open the space for dry land. In the Hebrew Bible the dome is called "raqi'a," meaning a firm substance, and rendered in the King James translation as "the firmament” The firmament in Biblical times was understood to be firm only by the will of God.

8. If God were angered, "the windows of heaven" and "the fountains of the deep” could burst open once again and those lovely blue waters would destroy the Earth. A painting by the American Edward Hicks (1780–1849), showing the animals boarding Noah's Ark two by two.

11. The orbital path of the Earth around the Sun is called the ECLIPTIC. • The Earth’s axis of rotation is tilted 23 ½ degrees with respect to the • ecliptic plane.

12. The orbit of the Earth around the Sun is not a circle; it is an ellipse

13. The Earth's rotation is counter clockwise looking down on the N pole, and results in the apparent motion of the celestial sphere -- everything rises in the East and sets in the west. 1 solar day = time from one noon to the next = 24 hours

14. Longitude and Latitude Longitude and latitude define your position on Earth. The zero of latitude is the Equator The zero of longitude is the prime meridian: line which passes through the old Greenwich observatory outside London, England. Tucson: Latitude 32 degrees North, Longitude: 110 degrees west

15. Astronomers define DECLINATION (Dec) and Right Ascension – these are coordinates like longitude and latitude but describe the position of stars, galaxies, etc on the celestial sphere. At the north pole of Earth:

16. Figure 2.4: As viewed from the Earth’s North Pole

17. Figure 2.3: The celestial sphere as a useful fiction

21. Circumpolar Stars Always above Horizon In the Northern Hemisphere, they Appear to rotate around The North Star, Polaris In the Southern Hemisphere, No bright star at rotation center

22. Figure 2.5: Our perspective on the sky depends on our location

23. Figure 2.9, Right: Celestial sphere at different latitudes

24. The orbital path of the Earth around the Sun is called the ECLIPTIC. • The Earth’s axis of rotation is tilted 23 ½ degrees with respect to the • ecliptic plane.

25. Figure 2.10: Earth’s orbit and constellations along the ecliptic The Zodiac = The constellations along the ECLIPTIC

26. Astrology and Horoscopes: • Assumption is that the position of the Sun and planets at the exact • moment of your birth determines what will happen in your life. • Horoscopes: very general statements that can apply to anybody. • What is the probability that 1/12 of the world’s people are • having the same kind of day? • Different schools of astrology contradict each other. Superstitions: Thinking that one action causes another when there is no actual connection c.f. B.F. Skinner’s pigeons and “pigeon religion”