The New Solar System Summarizes what we've learned from
interplanetary explorations in the last 25 years. My primary
reference for The Nine Planets. Encyclopedia of the Solar System
A more scholarly introduction the planetary science for those
who want to dig a little deeper. The Compact NASA Atlas of the
Solar System This 'road map' of the solar system contains lots
of maps and data as well as photos. RL = 2.456*R*(p'/p)^(1/3)
where p' is the density of the planet, p is the density of the
moon, and R is the radius of the planet. (more)