Chapter 13 – Lesson 2 Notes
A. The Moon and Earth (p.482-483)
1 . moon – any natural body that revolves around a planet
2. Similarities of Earth/Moon
a. rocky
b. fairly dense
c. made of same elements (aluminum, oxygen, calcium, silicon, iron)
d. have craters – low, bowl-shaped area on the surface of a
planet/moon
3. Earth’s Differences
a. larger in size (4x’s in diameter more than Moon)
b. stronger gravitational pull
c. has atmosphere
d. looks blue in space (due to liquid water on planet)
e. has liquid water / plant life
f. has erosion
4. Moon’s Differences
a. smaller in size
b. pull of gravity is 1/6 less than on Earth
c. almost no atmosphere (many more craters because lack of
atmosphere to burn them up before hitting surface)
d. looks gray (rocks/dust)
e. no liquid water / plant life
f. no erosion
g. extreme temperatures
B. Phases of the Moon (p.484-485)
1. Earth revolves around Sun / Moon revolves around Earth
a. orbits are ellipse in shape (egg-shape)
2. Earth/Moon rotate as they revolve
a. Moon rotates slower
b. takes 29½ days for Moon to complete rotation
c. same side of moon always faces Earth
3. Moon does NOT give off its own light
a. part of moon exposed to sun reflects sun’s light
b. at any time, ½ of moon lit by sun
c. way moon looks from Earth changes daily
4. moon phase – one of the shapes the moon seems to have as it orbits Earth
a. full moon – Earth is between moon and sun
b. new moon – moon is between Earth and sun
c. waxing phases – more of moon is visible from Earth each night
d. waning phases – less of moon is visible from Earth each night
5. Order of Moon Phases:
a. new moon, waxing crescent, first quarter, waxing gibbous, full moon,
waning gibbous, third quarter, waning crescent
b. takes 29½ days to complete cycle
Q: Contrast the appearance of the moon during a full moon and a new moon.
A: During a full moon, the moon is a complete glowing disk. During a new moon, you
can’t see any of the moon.
C. Eclipses (p.486)
1. eclipse – an event that occurs when one object in space passes through the
shadow of another object in space
2. Solar Eclipse:
a. occurs when new moon casts shadow on Earth
b. total solar eclipse covers only small part of Earth
c. during total solar eclipse – moon covers all of the sun
d. order: sun, moon, Earth
3. Lunar Eclipse:
a. occurs when full moon passes through shadow of Earth
b. Earth blocks sun’s light from reaching moon
c. moon does not look black – looks red because Earth’s atmosphere
bends red light
d. refraction – bending of light as it moves from one material to
another
e. order: sun, Earth, moon
4. Total solar/lunar eclipses – not too often
5. Partial solar/lunar eclipses – 2 to 4 times a year