asteroid- One of many small rocky bodies orbiting the Sun; a concentration of these makes up the asteroid Belt between Mars and Jupiter

basalt-Fine-grained igneous rock(rick in mafic minerals) that has erupted onto the surface

crater- An approximately circular depression, sometimes surrounded by a raised rim. craters are typically formed by explosion during meteorite impact

density-the average number of individuals or units per space unit

diameter-the length of a straight line through the center of an object

eccentricity- deviation from circular

inclination- a tilting of something; act or the action of bending

Jupiter- planet fifth in order from the sun. In Roman mythology, ruler of the gods(Greek name, Zeus)

Mars- planet fourth in order from the sun. In Roman mythology, god of war and discord(Greek name, Ares)

mass- expanse or bulk

mean-being near the average; occupying a middle position

mercury- the planet closest to the sun. In Roman mythology, the fleet-footed messenger god and escort of dead souls to the underworld(Greek name, Hermes)

Neptune-planet eight in order from the sun. In Roman mythology, god of the sea(Greek name,Poseidon)

obliquity-tilt of axis in degrees

orbit- to travel in circles;revolve; revolution

Pluto-planet ninth in order, and farthest, from the sun. In Greek mythology, god of the dead and the underworld

revolution-the action by a celestial body of going round in an orbit or elliptic course;circle(see orbit)

rotation- the action or process of rotating on or as if on an axis or center; one complete turn

satellite- a celestial body orbiting another of larger size

Saturn-planet sixth in order from the sun. In Roman mythology, god of agriculture, and father of Jupiter(Greek name, Cronos)

Uranus-planet seventh in order from the sun. In Roman mythology, god of the sky, mate of the goddess of the Earth, and father of the Titans

Venus-planet second in order from the sun. In Roman mythology, goddess of love(Greek name, Aphrodite)