click below
click below
Normal Size Small Size show me how
6th Unit 1-c
Solar System Key Terms
Term | Definition |
---|---|
asteroid | an irregularly shaped rock that orbits the Sun. |
comet | a space object made of ice and dust that orbits a star and develops a long, bright tail as it nears its star. |
core | the center of an object. |
crater | a hole in the ground caused by the impact of an object from space. |
dwarf planet | a nearly round object that orbits a star, is smaller than a planet, and is not a satellite of another object. |
gas giant | a large planet that is mainly made up of gases. |
gravity | the force that pulls all objects toward each other. |
moon | a huge ball of rock that travels around a planet; a natural satellite. |
orbit | to revolve around another object. |
planet | a very large object that orbits a star. |
satellite | a natural or human-made object that orbits Earth or another object in space. |
solar system | a group of objects in space that orbit a star |
star | a body in outer space, made of hot gases, that shines in the night sky. |
terrestrial | like Earth; describes planets that are rocky and Earthlike in size. |
asteroid belt | the area in space between Mars and Jupiter where most asteroids orbit. |
atmosphere | a layer of gases surrounding a planet, star, or moon. |
gas | a substance with no fixed volume or shape that can expand freely. |
helium | the second lightest chemical element; often a gas. |
hydrogen | the lightest chemical element; often a gas. |
mass | the measure of the amount of matter in an object. |
methane | a colorless, odorless, flammable gas commonly called "natural gas". |
oxygen | a gas that has no color, taste, or smell, and which people need to live. |