CHAPTER 24.4 EARTH-MOON-SUN SYSTEM

Learning Targets

1. Describe how Earth’s movement affect seasons and cause day and night

2. Explain solar and lunar eclipses3. Describe the phases of the Moon

and explain why they occur4. Explain how movements of the

Earth and Moon affect Earth’s tides

Earth-Moon-Sun System

1. Earth’s Rotation - Spin is counterclockwise when viewed from the North Pole

2. Sun, Moon, stars rise in the East and set in the West

Day-Night Cycles

1. Day: time required to rotate once2. Length determined by whether the

North or South is tilted toward the Sun

a) Longer days + Direct Sun = Summerb) Shorter days + Indirect Sun = Winter

3. Equator: equal day length all year4. Poles: six months day, six months

night

Seasons

1. Length of day changes with seasons2. Angle of sunlight changes with

seasons3. Sun directly overhead = More direct

light4. More direct light = More heat

a) Longer days + Direct Sun = Summerb) Shorter days + Indirect Sun = Winter

The path of the sun in the sky

Solar Eclipse

1. Moon moves between the Earth and Sun

2. Photosphere is blockeda) Corona becomes visibleb) Earth gets dark for a few seconds

3. Aug. 21, 2017

Lunar Eclipse

1. Earth between Sun and Moon2. Moon goes dark because it does not

make its own light3. Sep 28, 2015

Lunar Eclipse

1. The umbra is the inner, cone shaped part of the shadow, in which all of the light has been blocked.

2.Penumbra where only part of the light is blocked

Phases of the Moon

1. Moon reflects sunlight2. We only see the part of the Moon

that is both facing the Sun and the Earth

3. This means the visible portion of the Moon is constantly changing

The phases of the Moon

Tides

1. Caused by the Moon’s gravitational pull on the oceans

a) Sun also affects the tides

2. Spring tidea) Extreme tides; higher high, lower

low

3. Neap tidea) Moderate tides; lower high,

higher low