front 1 asteroid | back 1 a small rock body orbiting the sun. |
front 2 asteroid belt | back 2 A region of the solar system between the orbit of mar and Jupiter where many asteroids are found. |
front 3 atmosphere | back 3 A mixture of gases that surrounds a planet or moon. |
front 4 comet | back 4 A ball of frozen dust and rock that orbits the sun and has a tail that glows. |
front 5 crater | back 5 A large round pit caused by the impact of a meteoroid. |
front 6 galaxy | back 6 A collection of stars, dust, and gas bound together by gravity. |
front 7 gas giants (Jovian Planets) | back 7 The name given to the first four outer planets: Jupiter, Saturn, Uranus, and Neptune. |
front 8 gravity | back 8 A force that pulls objects toward each other. |
front 9 Planets | back 9 A celestial body moving in an elliptical orbit around a star. |
front 10 Moon | back 10 A natural object that orbits a planet. |
front 11 Milky way | back 11 The galaxy containing the solar system. |
front 12 Orbit | back 12 The path an object follows as it moves around another objects. |
front 13 Revolution | back 13 The movement of an object around another object. |
front 14 Rotation | back 14 The spinning motion of a planet on it axis. |
front 15 Solar system | back 15 The collection of eight planets and their and their moons in orbit around the sun. |
front 16 star | back 16 A ball of hot gas, primarily hydrogen and helium, that undergoes nuclear fusion. |
front 17 Terrestrial | back 17 The name of the inner planets. |
front 18 Dwarf Planet | back 18 A celestial body resembling a small planet but lacking certain technical criteria that are required for it to be classified as such. |
front 19 Light year | back 19 The distance light travels in one year. |
front 20 Kuiper Belt | back 20 A region of a solar system that is just beyond the orbit of Neptune |
front 21 Meteor | back 21 A small body of matter from outer space that enter the Earth's atmosphere appearing as a streak of light |
front 22 Universe | back 22 All of space and everything in it. |