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EARTH

WHAT IS EARTH?

What is Earth?

What is the earth made of?

Facts of Earth

Structure of the Earth

Earth Rotation and Revolution

What is Earth?

Earth is the third planet from the sun

What is the earth made of?

Structure of the earth

Earth Rotation

Rotation of the Earth

• Rotation means “to spin.” Earth rotates on its axis (an imaginary line running through the center of the Earth from the North Pole to the South Pole).

• Earth completes 1 rotation (spin) every 24 hours.

Day and Night

• Question: What causes day and night on Earth? • Answer: Day and night are caused by Earth’s rotation (spin)

on its axis. When ½ of the Earth is facing the sun it is DAY. When ½ of the Earth is facing away from the sun it is NIGHT.

Earth Revolution

Revolution of the Earth

• Revolution means “to go around something.”• A synonym for revolution is orbit. (revolution = orbit)• The Earth revolves (goes around) the sun counterclockwise.• It takes Earth 365 days (or 1 year) to make one complete

revolution around the sun.

The Seasons• Question: What causes the seasons on Earth?• Answer: Earth’s seasons are caused by 1) Earth’s titled axis

and 2) Earth’s revolution (orbit) around the sun. When the Northern Hemisphere(Half of the earth) is tilted toward the sun we have summer. When the Northern Hemisphere is titled away from the sun we have winter.

Facts of Earth

SPACEThere Are Not 24 Hours In a Day

23 hours, 56 minutes, and 4 second – the time it takes earth to rotate on its axis,

called sideral day

Earth Is Smoother than Bowling ballHigh mountains and deep ocean trenches

make up only 1/5000th of the earth circumference

1 Object a DayNASA (National Aeronautics and Space

Administration)estimates on average, that one piece of space junk returns to earth each day

ATMOSPHERE

100 TONSOf small meteorites mainly

fragments of dust , enter the earth’s atmosphere every day.

8.6 MILLIONLightning strikes a

day

The Ozon Hole Is ShrinkingIn 2012, the hole in the layer was smaller than it has ever been in

the last 10 year

SEAWATER ON EARTH IS

97% Salted3% Fresh

90%Of all volcanic activity occurs in the ocean

10.9 KMThe depth of the deepest area of the

ocean : The Mariana Trench

UNDER EARTHEarth Is The Only Planet in our Solar

System with plate techtonicWithout them, carbon wouldn’t be

consumed and recycled. And the earth would overheat (just like Venus)

99% of Earth’s Gold lies in its CoreEnough to form 1.5-foot coat around the

surface of the earth.

2.8 KM/1.7 MILESThe depth at witch bacteria have

been found. They survive by using radioactivity from uranium to

convert water to usable energy

Message from Earth