1. Earth review 1.Difference between rotation and revolution 2.How long is Earth’s rotation? Revolution? 3.What causes seasons?

2. The M N

3. The Moon Large chunk of rock that goes around the Earth in an orbit. Planets orbit stars, Moons orbit a planet First visited by USSR’s robotic spacecraft in 1959 Has no moon of its own; no ring Has a very thin and weak atmosphere + lack water  can’t support life Mass =7.345 × 10 22 kg Earth- Moon distance: 384,400 km (how many AU?) Answer= 0.00257 AU.

4. How was the Moon formed? -Over 4.5 billion years ago, a Mars-sized body collided with the still-molten Earth -debris from the collision accumulated into Earth’s Moon. -Bombarded by asteroids, meteoroids and comets over billions of years  Moon’s surface ground up and “scarred” with craters Source: "How the Moon Formed." : Melbourne Museum. N.p., n.d. Web. 26 Mar. 2015.

5. First human visit: 1969 Neil Armstrong, Buzz Aldrin and Mike Collins (Apollo 11) Astronaut’s footprint Thin atmosphere & no moisture  stayed preserved The Moon Buzz Neil MIke

6. How the Moon looks depend on where we view it on Earth : Viewed from the North pole from outer space Viewed from the center of its orbit (i.e. from Earth) We see different portions of the lit side of the Moon.

7. Moon’s synchronous rotation Moon rotates once on its axis every 27.3 days. Time taken the moon to orbit Earth also 27.3 days (i.e. called orbital period)  scientists called this synchronous rotation https://www.youtube.com/watch?v=OZIB_leg75Q The Earth and the Moon rotate and revolve counterclockwise

8. Seen before? When? Only occurs at night? What happens to the Moon in the morning? Answer: no; the moon is always there. In the morning it’s harder to view due to the over- powering brightness of the Sun

9. Moon cycle: 29.5 days (~ one “moonth”; from one new moon to the next) Moon phase explained: 1. http://video.nationalgeographic.com/video/101-videos/moon-101-sci http://video.nationalgeographic.com/video/101-videos/moon-101-sci 2. https://www.youtube.com/watch?v=Jip3BbZBpsM 8 main phases View from space

10. When Sun, Earth, and Moon are 180 o C to each other (all on a straight line):full or new moon When Sun, Earth, Moon are at 90 o to each other: 1 st and last quarter; moon half lit -New moon : when moon between Sun and Earth -Full moon: when moon behind Earth, with respect to the Sun - Gibbous = between half lit and fully lit - Waxing = increasing; Waning= decreasing Play animation http://astro.unl.edu/classaction/animations/l unarcycles/lunarapplet.html

11. Group work: Make a Moon phase profile Note: "first quarter" = one-quarter of the monthly cycle elapsed; not “¼ of the moon is being lit”  Meaning of “third quarter“? With entertainment: https://www.youtube.com/watch?v=79M2lSVZiY4 https://www.youtube.com/watch?v=ABM_8IVFE6k

12. Shadow: Umbra and Penumbra Umbra = the inner shadow Penumbra = the outer shadow Earth’s shadow Moon

13. Tides, Lunar eclipse vs Solar eclipse What you’ll need:  Textbook page 287-289  Comparison chart from Ms. Pham  Your partners Read p283-290 Answer p285 #1-4; p288 #5-8; p290 #2-6,8 Today’s HW