one of the dense rocky planets nearest to the sun; Mercury, Venus, Earth, Mars
the counterclockwise spin of a planet or moon seen from above its North Pole.
the clockwise spin of a planet or moon seen from above its North Pole.
a planet that has a deep massive atmosphere; Jupiter, Saturn, Uranus, Neptune
a small body of ice, rock, and cosmic (space) dust loosely packet together that orbits the sun and forms a tail as it passes close to the sun.
a small rocky object that orbits the sun, usually in a band between the orbits of Mars and Jupiter
a small rocky body that travels through space.
a meteoroid that reaches Earth's surface
a bright streak of light produced when a meteoroid burns up in Earth's atmosphere
a system by which scientists rate the hazard (danger) level of an object moving toward Earth; 0=small chance of reaching Earth 10 = definitely reaching Earth