1. The Solar System
By Level Two

2. The Sun The sun is 864,000 miles in diameter The sun is a star
The temperature on the sun’s surface is 10,500 degrees Fahrenheit
The sun is the brightest object in the sky
The sun is made of hydrogen and helium

3. The Milky Way The Milky Way is made out of light
The Milky Way is 100,000 light years across from end to end
The Milky Way is a galaxy- a huge ground of stars and other objects in space
The best time to see the Milky Way is during winter
The Milky Way does not orbit the sun because it is a galaxy

4. Mercury Mercury is 3,031 miles in diameter
Mercury is made up of rocks and iron
Mercury is covered in a thin layer of minerals.
It takes Mercury two years to orbit the sun
Mercury is 36 million miles from the sun

5. Venus The diameter of Venus is 7,521 miles Venus is made out of rocks
It takes 225 days for Venus to orbit the sun
Venus and Earth are the same size
Venus does not have any moons

6. Earth
Earth is 7,927 miles in diameter Earth is made out of rocks Earth is one of the rockiest planets Earth is sometimes called the “blue planet” People once thought that the Earth was the center of the solar system

7. Mars Mars is 4,292 miles in diameter Mars is made out of gas
People can see Mars in the night sky during certain times of the year
Mars is smaller than the Earth
From Earth, Mars looks like a bright red star

8. Jupiter Jupiter is 88,850 miles in diameter Jupiter is made out of gas
It takes Jupiter 9 hours and 55 minutes to rotate
Jupiter has three rings
Jupiter has 16 moons

9. Saturn The diameter of Saturn is 74,899 miles
It takes Saturn 29 years and 6 months to orbit the sun
Titan is Saturn’s largest moon
Saturn is not heavy compared to its size
Five of Saturn’s moons are less than 20 miles long
Saturn is made out of gas

10. Uranus The diameter of Uranus is 31,764 miles
It takes 84 years for Uranus to orbit the sun
Uranus has 18 moons
In 1977 Uranus passed in front of a star
People knew very little about Uranus before 1977
Uranus was the first planet discovered since ancient times

11. Neptune The diameter of Neptune is 30,776 miles
Neptune is made out of gas
The great dark spot has disappeared from Neptune’s atmosphere
Bright blue clouds surround Neptune
Neptune’s air has no oxygen

12. Pluto The dwarf planet Pluto was discovered in 1930
The diameter of Pluto is 1,422 miles
Pluto is made from rocks
It takes Pluto 248 years to orbit the sun
Pluto is a far-off icy body in our solar system
Pluto comes closer to the sun than the planet Neptune

13. Asteroids Asteroids are made out of rocks
Some asteroids follow the planet Jupiter around the sun
Asteroids are found between Mars and Jupiter
Asteroids are less than 18 miles in diameter
The best time to view an asteroid is at night with a telescope

14. Comets A comet can move up to one million miles per hour
The path of a comet is a flatten circle
When the comet is towards the sun, the tail is behind the head
A comet moves fast in its trip around the sun
A comet is made out of gases and dust