Solar System

1. a physical property of matter that describes the amount of mass in a unit of volume
3. a celestial object that directly revolves around the sun, has a nearly spherical shape, but has not cleared the neighborhood around its orbit
8. the distance from the center of the planet's core to the outer edge of its atmosphere
12. a star and all the objects that travel around it
14. a unit of measurement equal to the average distance between Earth and the sun; about 150 million km
15. a small object made of rock, ice, and dust that has a highly elliptical orbit around the sun and gives off gas and dust in a tail as it travels close to the sun
16. a celestial object that indirectly revolves around a star
17. the level of measurement being used

2. a planet that has a hard, rock surface
4. a representation of a system that has the same relative sizes or distances as the actual system
5. an attractive force between all objects that have mass
6. a planet that has a deep atmosphere and no rocky surface
7. a telescope that is located in outer space
9. the average distance at which a planet revolves around the sun
10. a small rocky or metallic object that revolves around the sun
11. an object that directly revolves around a star, has a nearly spherical shape, and cleared the neighborhood around its orbit
13. information collected that can be used to support explanations