The Solar System

1. The Solar System A Fifth Grade Science

2. Introduction • A solar system consists of a star and objects that revolve around it. • Our Solar System consists of the Sun and nine known planets and the moons that orbit those planets. • The force of gravity keeps planets in orbit around the sun.

4. The Sun • It is over one million times larger than Earth. • It is eight light minutes away from Earth or 92,957,000 miles. • The temperature is 15 million degrees K. One K = 13-25 million degrees!

5. Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto The Nine Known PlanetsThe Inner PlanetsThe Outer Planets

6. Mercury • Closest planet to the sun • Approximately half the size of Earth • Rocky surface covered by craters • No water or air results in unchanged appearance • Surface temperatures are hot enough to melt lead

7. Uranus • Seventh planet from the Sun • Four times larger in diameter than the Earth • Blue-green in color • The tilt of the axis causes sunlight for 42 years at a time

8. Venus • Second planet from the Sun • Approximately the same size as the Earth • Atmosphere consists of poisonous gases

9. Earth • Third planet from the Sun • Largest of the four inner planets • Only planet where life is known to exist • 70% of the surface is covered by water

10. Mars • Fourth planet from the Sun • Approximately half the size of Earth • Known as the Red Planet • Has four seasons similar to Earth • Resembles Earth more than any other planet

11. Jupiter • Fifth planet form the Sun • Largest planet in our Solar System • 1300 Earths could fit inside Jupiter • Doesn’t have a surface; made of gases

12. Saturn • Sixth planet from the Sun • Second largest planet • 800 Earths could fit inside Saturn • Thousands of rings are made up of ice and rock fragments

13. Neptune • Eighth planet form the Sun • Four times larger in diameter than the Earth • Blue in color

14. Pluto • Ninth planet from the Sun • Smallest of the planets • Coldest planet • Unusual orbit caused it to be the 8th planet from 1979 - 1999!

15. Let’s compare the planets to Earth

16. A day on : Mercury = 3 Earth months Venus = 117 Earth days Mars = 41 minutes longer than an Earth day Jupiter = 10 Earth hours Saturn = 10 ½ Earth hours Uranus = 13 ½ Earth hours Neptune = 18 Earth hours Pluto = 7 Earth days

17. If you weigh 85 lbs. On Earth, you weigh: • 32 lbs on Mercury • 77 lbs on Venus • 32 lbs on Mars • 244 lbs on Jupiter • 112 lbs on Saturn • 79 lbs on Uranus • 105 lbs on Neptune • 2.5 lbs on Pluto

18. The Orbital Speed of the Planets • Mercury = 30 miles per second • Venus = 22 miles per second • Earth = 19 miles per second • Mars = 15 miles per second • Jupiter = 8 miles per second • Saturn = 6 miles per second • Uranus = 4.2 miles per second • Neptune = 3.3 miles per second • Pluto = 2.9 miles per second Therefore, the further away from the Sun, the slower the orbital speed.

19. The Earth has one Moon.How many moons do the other planets have? • Mercury - 0 • Venus - 0 • Mars - 2 • Jupiter - 17 • Saturn - 22 • Uranus - 15 • Neptune - 2 • Pluto - 1 • The Moon

20. It takes 365 days for Earth to revolve around the Sun. How long does it take the other planets? • Mercury - 88 Earth days • Venus - 225 Earth days • Mars - about 2 Earth years • Jupiter - 11.8 Earth years • Saturn - 30 Earth years • Uranus - 84 Earth years • Neptune - 165 Earth years • Pluto - 248 Earth years