SCI 1000C Lecture Notes - Lecture 4: Celestial Pole, Celestial Equator, Tidal Locking
4 Feb 2020
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Document Summary
Explain the apparent motion of the sun, moon, and stars. Use a simple model of the earth, sun, and moon to explain why phases of the moon, eclipses, and seasons occur. Parallax is useful for distances up to about 10,000 light years. Beyond that, the apparent change in angular position is too small for telescopes to resolve. The earth rotates (spins around its poles) once per day. The earth revolves around the sun (makes one complete orbit) once per year. The moon revolves around the earth once every 27. 3 days. Stars we see are part of our galaxy, the milky way. Zenith - the point in the sky directly above your head. Horizon - defined by pointing perpendicular to zenith, in any direction. Meridian - the arc that runs from north to south through your zenith. Celestial sphere - we can use the earth as a reference for a more objective way to describe the solar system.
