Earth’s Moon (aka. Luna)

Cornell Notes page 69“How does the moon affect the

earth?”

How far away is the MOON?

• 380,000 km (about 239,000 miles)

What is a SATELLITE?

• A natural or man made object that revolves around a planet

• (A natural satellite is a MOON)

What is the moon doing out in space?

• Revolving around the Earth in a counterclockwise direction

• Rotating on its axis as it goes around the Earth

Where did the Moon

come from?

Giant Impact Theory

• Earth struck by large body, size of Mars.

• Part of body + Earth flung into space.

• Captured by gravity of Earth.

What is Gravity?

• Natural phenomenon by which all physical bodies (anything with mass) attract each other

• holds celestial bodies together

• keeps celestial bodies in orbit

What effect does the moon have on Earth?

• Tides- • rise and fall of water levels due to gravitational forces

• Occur twice a day (2 high tides, 2 low tides)

http://home.hiwaay.net/~krcool/Astro/moon/moontides/

high tide

low tide

How are Tides created?

• (3 ways)1. Because the Earth

and the moon are attracted to each other

http://home.hiwaay.net/~krcool/Astro/moon/moontides/

Moon and earth are attracted to each other by gravity

Tides are also created by:

•2. the rotation of the earth

•3. and the sun’s gravity

The sun can affect the tides, too

Spring Tides

Tides are not waves!

What are Spring tides?

• Tides that produce the greatest difference between high and low tides—The biggest tides

• Occur twice a month

When do spring tides occur?

• Once at the full moon and once at the new moon

• When the sun moon and earth are nearly in a lineSpring Tides combined with big storms

Spring Tides –the sun

and the moon line up

What are NEAP Tides?

• Tides that produce the least difference between high and low tides—The smallest tides

• Occur twice a month

When do neap tides occur?

• Once at the first quarter and once at the third quarter

• When the sun moon and earth are at right angles to each other

http://www.space.gc.ca/asc/eng/educators/resources/astronomy/multimedia/module3/tides/tides.swf

The neap tides –the smallest tides –when the sun and moon are at a 90 angle

•What other effects do we have from the moon??