| A | B |
|---|
| sun | The star at the center of our solar system |
| Planets | Major bodies that orbit a star |
| moon | A natural satellite that revolves around a planet. |
| Earth | 3rd planet from the sun |
| law of universal gravitation | the scientific law that states that every object in the universe attracts every other object; the variables of mass and distance affects the strength of the force |
| Atmospheric conditions | temperature, precipitation, wind, humidity, air pressure |
| Speed | The distance an object travels per unit of time |
| Heliocentric | Based on the belief that the sun is the center of our solar system |
| Geocentric | A model of the universe in which Earth is at the center of the revolving planets and stars. |
| Orbit | The elliptical path of an object as it revolves around another object in space, determined by gravity |
| Variables of Gravity | distance and mass |
| spherical | the shape of planets, moons, and stars; determined by gravity |
| landscape | the description of the surface of a planet which may be smooth, have mountains, craters, volcanoes, or other features |
