| A | B |
|---|
| solar system | the Sun and all the planets are effected by its gravity |
| Pluto | a dwarf planet in the solar system that is smaller than some moons in the solar system |
| planet | an object in orbit around a star, is nearly round, and has cleared other objects from its orbit |
| dwarf planet | an object in orbit around a star and is nearly round; it doesn’t clear objects from its orbit like planets |
| asteroid | a rocky object orbiting the Sun |
| comet | an object with a long tail orbiting the Sun |
| terrestrial planets | any of four planets nearest Sun |
| gas giants | a large planet composed mostly of gaseous material |
| Mercury | a heavily cratered planet that looks like our moon and is the smallest planet in our solar system |
| Venus | a planet similar to Earth in size and mass, that has a permanent blanket of clouds that trap so much heat that the temperatures on the surface are hot enough to melt lead |
| Earth | a planet that supports life because of its atmosphere, liquid water and its distance from the sun |
| Mars | a planet that has a thin atmosphere and a vast network of canyons and riverbeds that is sometimes called the red planet |
| Jupiter | the largest planet in the solar system, a gas giant with no solid surface that has faint rings made of dust |
| Saturn | the second largest planet, one of the gas giants, that has bright visible rings made of rocks |
| Uranus | a gas giant with rings made of ice particles |
| Neptune | a gas giant that appears blue through telescopes, with rings made up of dust |
| Sun | the star that is the central body of the solar system |
