Superior vs. Inferior Planets
•Superior planets (Mars, Jupiter, Saturn, Uranus, Neptune, Pluto) have orbits larger than the earth and can appear opposite the sun in the sky.  They can be up at midnight.  Never show phases.
•Inferior planets (Mercury, Venus) have orbits smaller than earth and can never appear far from the Sun.  They form “morning stars” or “evening stars” visible a little before sunrise or after sunset.  Show phases.
From our text:  Horizons, by Seeds