The Moon

Phases and TidesVsauce: Who owns the Moon?

Moonlight

Five friends noticed they could see better at night when there was a full Moon. They wondered where the moonlight came from. This is what they said:

Curtis: “The Moon reflects the light from the Earth.”

Chet: “The light from the Sun bounces off the Moon.”

Clarence: “The Moon gets its light from distant stars.”

Fallon: “The Moon absorbs light from the Sun during the day.”

Deirdre: “There is light inside of the Moon that makes it shine.”Which person do you most agree with? Explain your thinking about moonlight.

How did the Moon form?

According to the giant impact hypothesis, the Moon formed about 4.6 billion years ago when an object about the size of Mars collided with Earth.

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A large object collided with Earth.

The collision caused a mass ejection of

material from the Earth.

The ejected material was pulled into orbit around the Earth. It eventually clumped together, cooled down and solidified to

make the Moon we have today.

Moon Data

Mass Diameter Distance from Earth

Period of Rotation

Period of Revolution

1.2% of Earth’s mass

(7.347 x 1022 kg)

27% of Earth’s diameter

(3,474 km)

384,000 km 27.3 days 27.3 days

Surface of the Moon

CRATERSDepressions that were formed when objects from space crashed into the

Moon. Surrounded by rays (streaks) that show where material was ejected

MARIALarge, dark, flat areas that

formed when lava flowed up through the Moon’s crust and

solidified.

HIGHLANDSLight colored areas that were too high for the lava to reach.

Why does the Moon have

so many craters?

Because it lacks an atmosphere to

protect it!

Can you identify craters, maria and highlands?

maria

crater

highlands

NASA Tour of the Moon

Why does the moon look different throughout the month?

We can only see the part of the moon that is illuminated by the Sun and at the angle visible from Earth.

The different appearances of the moon is what we call the phases of the moon.

BrainPOP: Moon Phases

Moon Phases

Visualize it!

1. Why does the Moon look different throughout the month?

2. Name the phase that occurs when the Moon is between Earth and the Sun.

3. Name the phase that occurs when the earth is between the Sun and the Moon.

Exit Slip: The Moon

Two types of Eclipses

Lunar Eclipse

• Occurs only during a FULL moon.

• The Earth casts a shadow on the moon and the moon

appears to be covered (turns red).

Who can see it?Anyone who is on the nighttime side

of the Earth during the eclipse!

Solar Eclipse

• Occurs only during a NEW moon.

• The moon casts a shadow on Earth, blocking the sunlight.

This makes it look like the Sun is covered.

Who can see it?Anyone who is on the daytime side of the

Earth that is being covered by the moon’s shadow!

Why is the lunar eclipse red, you ask??

During the lunar eclipse, the moon will still get some indirect sunlight ,even though its in

Earth’s shadow. This light is deflected by the atmosphere, causing only the red and orange

wavelengths of light to get through.

When is the next lunar eclipse?

April 15th, 2014TOTAL LUNAR ECLIPSE

Starts at about 1:00am with the total eclipse experienced at 3:45am.

Solar Eclipse in Australia

The position of the Moon during its tilted

orbit has to line up just right with the Earth

and Sun for eclipses to occur. Otherwise, the

shadows miss each other.

Why is it dangerous to look at a solar eclipse?

During a solar eclipse, the Sun’s

brightness is reduced, and so is the discomfort

on your eyes. This is where the

danger lies because although it doesn’t hurt to look at it, the Sun can still damage

your eyes.

When is the next solar eclipse?

October 23rd, 2014PARTIAL SOLAR ECLIPSE

What are tides?

The daily cyclic rise and fall of Earth’s ocean surface caused by gravitational forces between the sun, moon, and Earth.

*cyclic= occurring in cycles

High tide: ocean water moves toward the shore. Low tide: ocean water moves away from the shore.

What causes the tides?

On the side of the Earth facing the moon, the gravitational force of the moon pulls the ocean’s waters toward it, creating one bulge. On the other side of

the Earth, inertia is greater than gravity of the moon, thus, creating a second bulge.

Did you know…

The moon’s gravity also pulls the solid Earth toward it?

Rocks can move up to 30 cm due to this.

Animation: High Tide/Low Tide

We experience two high tides and two low tides everyday!

The Sun also affects the tides…

When the Sun and Moon are aligned, the Earth experiences its highest and lowest tides. This is called SPRING TIDE.

Fun FactThe Bay of Fundy in Nova Scotia has the

highest tides in the world (more than 50 ft!!)

Bay of Fundy's tides

High Tide and Low Tide

4. What causes Earth’s ocean tides?

5. Draw a diagram that shows the position of the Earth, Moon and Sun when we experience the highest tides of the year (spring tide).

Exit Slip: The Moon