2. THE SOLAR SYSTEM

3. THE NINE PLANETS

4. THE INNER PLANETS The solar system is divided into two groups of planets - inner and outer. Inner planets are called terrestrial planets because they are like Earth - small, dense, and rocky.

5. MERCURY Mercury is the closest planet to the sun Mercury has very drastic temperature differences (-173 to 427ºC ).

6. VENUS Venus rotates in the opposite direction than Earth does. On Venus, a day is longer than a year.

7. EARTH Earth can support life because it has liquid water. A revolution around the sun is 365 ¼ days so every 4 years there is a “leap day” to catch us up..

8. MARS Mars is known as the “red planet.” Mars has a very thin atmosphere and low pressure.

9. THE OUTER PLANETS All of the outer planets are gas giants. Gas giants are very large planets that don’t have any known solid surfaces.

10. JUPITER Jupiter is mostly made of H and He and is the largest planet. The Great Red Spot is a giant storm about 1½ times the size of Earth.

11. SATURN The 2nd largest planet in the solar system Saturn has the largest rings of all of the planets that consist of icy particles.

12. URANUS An unusual quality of Uranus is that it is tipped over on its side (it is thought to have been hit by a massive object that tipped it over).

13. NEPTUNE Neptune’s atmosphere contains belts of clouds. Neptune has a set of very narrow rings.

14. THE SUN The sun is a large ball of gas made mostly of hydrogen and helium held together by gravity.

15. COMETS A comet is a small body of ice, rock, and cosmic dust loosely packed together.

16. ASTEROIDS & METEOROIDS Asteroids and meteoroids are small, rocky bodies in orbit around the sun, but meteoroids are much smaller.

17. THE END