Definitions
the spinning of Earth on its axis
What is rotation?
the closest star to Earth and the center of our solar system
What is the Sun?
Planets with an orbit outside of the asteroid belt
a force of attraction between two masses
What is gravity?
a large, gaseous, self-luminous body held together by gravity and powered by thermonuclear reactions
What is a star?
the study of the Universe, and everything in it
the imaginary line on which an object rotates
an object that orbits a planet
What is a satellite?
a star and all of the planets and other bodies that orbit it
What is the solar system?
the path that one object in space takes around another object in space
What is orbit?
a large body in space that orbits a star and does not produce its own light
any of the four planets whose orbit lies closest to the Sun and are within the asteroid belt
What are the inner planets?
a natural satellite that revolves around a planet
What is moon?
completing a fixed course
What is revolution?
any piece of comet, meteoroid, or asteroid that travels into Earth's atmosphere
What is a meteor?