2. The Solar System A Fifth Grade Science

3. 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.

5. 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!

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

7. 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

8. 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

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

10. 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

11. 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

12. 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

13. 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

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

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

16. Let’s compare the planets to Earth

17. 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

18. 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

19. 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.

20. 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

21. 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