| A | B |
|---|
| Pluto | the only planet discovered in the 20th century |
| Neptune | gas planet named for the Roman god of the sea |
| Uranus | gas planet that spins on its side- has 11 thin rings |
| Saturn | gas planet that has the most moons--also has hundreds of rings |
| Jupiter | largest of the gas planets - has a Great Red Spot |
| Mars | "The Red Planet" |
| Earth | the only planet that can sustain life |
| Venus | "Earth's Twin" - also known as the morning or evening star |
| Mercury | the planet closest to the sun |
| asteroid belt | area of rocks and debris between Mars and Jupiter |
