Term | Definition |
ROTATION | the spin of an object in space ( Note: Period of rotation is the amount of time it
takes for an object to make one complete rotation.) |
REVOLUTION | the elliptical motion of a body as it travels around another more massive body
in space (Note: Period of revolution is the amount of time it takes for one object to revolve
around another object.) |
ORBIT | the elliptical PATH an object takes in space while revolving around another object |
GRAVITY | attracting force due to mass or rotation |
ATMOSPHERE | mixture of gases that surrounds a planet |
SUN | a medium sized star; the center of our solar system |
PLANET | body that orbit around the sun or a star and does not produce its own light |
TERRESTRIAL PLANET | a small, dense, rocky planet similar to Earth (Inner planets) |
GAS GIANT | a large, gaseous planet of the outer solar system with no known solid surface
(Outer planets) |
NATURAL SATELLITE | smaller body that orbits around a larger body |
MOON | a natural satellite of a planet (Note: satellites are natural or artificial bodies that
revolve around more massive bodies such as planets) |
ARTIFICIAL SATELITE | any human made object placed in orbit around a body in space |
COMET | a small body of ice, rock, and cosmic dust loosely packed together |
ASTEROID | a small, rocky body that revolves around the sun |
MEDEOROIT | a meteoroid that reaches Earth’s surface without burning up completely HINT: It
takes the “right” path to Earth |
METEOR | a bright streak of light caused when a meteoroid or comet dust burns up in the
atmosphere NOTE: Many people call this a “shooting star”, but it is not) |
THRUST | the force that accelerates a rocket |
ORBITAL VELOCITY | the speed and direction a rocket must have in order to orbit Earth |
ESCAPE VELOCITY | the speed and direction a rocket must have in order to completely break
away from a planet’s gravitational pull |
CENTRIPETAL FORCE | the force that causes an object to follow a curved path |