1. Sunday, September 7 th, 2008 SPACE The Solar System

2. Our Solar System The center of our solar system is the sun. The sun is massive! It is so big that all of the other planets combined only make up 0.14% of the sun’s mass! All of the planets, comets, and meteors revolve around the sun because of the gravitational pull created by this huge mass.

3. Planets There are 8 planets in our solar system revolving around the sun. Planets - bodies that move around the sun and do not give off their own radiation (their own light). We can see the planets because the sun’s light reflects off of them

4. The eight planets are: My Very Eager Mother Just Served Us Nachos! MERCURYVENUSEARTHMARSJUPITERSATURNURANUSNEPTUNE

5. Rocky planets The four planets closest to the sun are rocky planets. Mercury, Venus, Earth and Mars all have rocky crusts.

6. Gas Giants The next four planets are all made of gas and are called the gas giants because of how big they are. Jupiter, Saturn, Uranus and Neptune are all made of gas.

7. Moons All of the planets, except for Mercury and Venus, have at least one moon. Moon – a body that revolves around a planet instead of the sun. Moons do not give off their own radiation (their own light) either.

8. Asteroids, Comets, and Meteors There are other bodies trapped by the sun’s gravity besides planets. Asteroids, comets, and meteors also revolve around the sun.

9. Asteroids Asteroid - one of the many small or minor rocky planetoids that are members of the solar system and that move in elliptical orbits primarily between the orbits of Mars and Jupiter.

10. Meteoroid Meteoroid - solid body orbiting the sun, becoming a meteor, or shooting star, if it enters the earth's atmosphere. The vast majority of meteroids are the size of grains of dust, but they range upward in size without any definite limit. The largest can have masses of thousands of tons.

11. Meteors and Meteorites Technically, a meteor is merely the streak of light we see trailing a meteoroid. A meteoroid is any interplanetary object bigger than a speck of dust and smaller than an asteroid. Once it hits Earth, a meteoroid suffers an identity crisis and becomes a meteorite.

12. Comets Comet - a relatively small, icy body revolving around the Sun. When a comet nears the Sun, some of the ice in the comet turns into gas. The gas and loose dust freed from the ice create a long, glowing tail that streams behind the comet.

13. Solar System Jigsaw – test yourself!