6. Which of the following people should be credited with formulating a new model for the solar system instead of merely refining an existing one
7. Planet X has a mass of 20 earth masses and a radius of 4 earth radii. These global properties are similar to
8. When the Moon rises at sunset its phase is
9. If you view the Sun from Skinner Butte Park at noon on Dec 21, approximately how many degrees above the horizon will the Sun be?
10. According to Kepler's third law strictly tells us that the orbital period of a planet depends on