front 1 Asteroid | back 1 A small rocky body orbiting the sun. |
front 2 Asteroid belt | back 2 The region of the solar system between the orbits of Mars and Jupiter. |
front 3 Atmosphere | back 3 A mixture of gasses 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. |
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 | back 7 The outer planets. |
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 the sun. |
front 10 Moon | back 10 A natural object that orbits a planets. |
front 11 Milky Way | back 11 The galaxy containing the solar system. |
front 12 Orbit | back 12 The movement of an object around another object. |
front 13 revolution | back 13 The path an object follows as it moves around another object. |
front 14 Rotation | back 14 The spinning motion of a planet on its axis |
front 15 Solar System | back 15 The collection of eight planets 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 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 the solar system that is just beyond the orbit of Neptune. |
front 21 Meteor | back 21 A small body of matter from outer space that enters the Earth's atmosphere appearing as a streak of light. |
front 22 Universe | back 22 All do space and everything in it. |