|DATABASE > DATABANKS > PLANETS > Class D - Geo Plastic|
Have mass of 1/100 to 1/1000 Earths and diameter of at least 500km. Orbit as planet or moon withing sun's habitable zone. Atmosphere is tenuous (if any), but water ice may exist beneath the surface and in permanently shaded craters. Earth's moon Luna and the asteroid Ceres are this class.