ASTRO-110 Lecture Notes - Lecture 2: Celestial Equator, Lunar Phase, Orbital Period
Document Summary
Stars remain fixed on the celestial sphere, but all appear to be rotating about us with the celestial sphere the north star , polaris, is very near the north celestial pole and moves very little (not always) Main factors associated with sun that determine warmth on earth. Distance of earth from the sun the angle of the sun in the sky. Which is most relevant to our day to day experience tilt and angle of the sun in the sky. When the sun is high, it warms more directly and efficiently summer. Winter point where sun crosses the meridian is low. Changing angle of the sun reason for seasons. Celestial event associated with the beginning and end of a year important in history (seasons) to figure out planting crops and when. Winter solstice and summer solstice lowest/highest points on meridian. Marks one year (maximum angles of the sun) Rough mark of one month the lunar cycle.
