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 = million degrees!

5. The Eight Known Planets The Inner Planets The Outer Planets
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune

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 Is now known as a “dwarf” planet Coldest planet
Unusual orbit caused it to be the 8th planet from !

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
It takes 365 days for Earth to revolve around the Sun. How long does it take the other planets?
Mercury Earth days
Venus Earth days
Mars - about 2 Earth years
Jupiter Earth years
Saturn Earth years
Uranus Earth years
Neptune Earth years
Pluto Earth years