Students model the planets in their actual positions around the Sun, incorporate the geometry of viewing parameters from Earth and visualize where planets will be seen (if visible) in the night sky on any given date. Materials Circular piece of wood or particleboard, 0.5 inches thick and 12 inches in diameter, with a pre-drilled center hole Wood dowel, at least 6 inches in length, to fit center hole of round wood panel board Circular protractor Dark-colored felt-tip permanent marker String Scra