Planet Earth

Section 1 Pages 33-36

A Geograpic View

"The earths great beauty resembles a blu and white marble,with contrasts of water and land beneath huge swirls of white clouds.Together these features form the physical environment of the earth."

Page 33

Our Solar System

"Earth is part of our solar system, which is made up of the sun and all of the countless objects that revolve around it.

At least 9 planets exist ,and each is in its own orbit around the sun.

The planets vary in size , Jupiter is the largest .Earth ranks 5th in size among the planets , and distant Pluto is the smallest .All the planets except Mercury and Venus have moons .

Earth has 1 moon , and Saturn has at least 18 moons .All planets except Pluto are grouped into two-types Terrestrial planets and Gas Giant planets

Mercury,Venus,Earth,and Mars are called Terrestrial planets For thier solid rocky crust.

Jupiter,Saturn,Uranus,and Neptune are Gas Giant planets for being farther away from the sun.

Asteroids,Comets,and Meteroroids revolve around the sun.Asteroids are small,irregular shaped,planetlike objects. Comets are made of icy dust particles and frozen gages , look like bright balls with long feathery tails.Meteroids are pieces space debris chunks of rock and iron

Water , Land And Air

The surface of the Earth is made up of around 70 percent water, and about 30 percent land. Oceans, lakes, rivers and other bodies of water make up a part of the Earth called the hydrosphere.

About 30 percent of the Earths surface is land, including continents, and islands which is lithosphere.

The air we breathe is part of Earths atmosphere, which is composed of 78 percent nitrogen, 21 percent oxygen, and small amounts of argon and other gases.

All humans, animals, and plants live on earths surface, close to the surface or atmosphere. The part of the Earth that can support life is the biosphere.