PHYSICS 20A Lecture Notes - Lecture 1: Diurnal Motion, Tropical Year, Northern Hemisphere
22 Jan 2018
School
Department
Course
Professor
Document Summary
Celestial - of the sky; of the part of the sky commonly observed in astronomy (looks at the universe as a whole, touches upon modern astronomy) The apparent motions of the sun, moon, stars and plants. Observation: the sun rises and sets w/ regularity. The time between successive periods of high noon is very regular. Apparent solar day - time between consecutive periods of high noon. Observation: the average weather, local temperature, changes slowly but regularly over many days. The position of sunrise changes slowly but regularity over many days. Horizon - the line of which the earth and sky appear to meet (limit of human vision on ground in a circle around them) Zenith - point on the sky directly overhead. Azimuth -angle around the horizon ( measured north through east) equals o defined as the point on the horizon which intersects the meridian containing the zenith and the north pole (polaris)
