ASTR 3 Study Guide - Midterm Guide: Celestial Pole, Celestial Equator, Minute And Second Of Arc
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What is the definition of a light year (recall: c=3x10^5 km/s) . 31,560,000 seconds in a year (60 seconds x 60 minutes x 24 hours x 365 days) On a scale in which the sun is the size of a grapefruit, earth is the size of a ballpoint from a pen, orbiting the sun at a distance of 15 meters. Similar to latitude, it"s the angle above or below the celestial equator. The path the sun follows as it appears to circle around the celestial sphere once a year. it crosses. 1 degree = 60 arcminutes = 3600 arcseconds. Define these terms relevant to your local sky: altitude, azimuth, meridian, zenith. Called direction, direction around the horizon from due north, measured clockwise in degrees, Azimuth for example, the azimuth of due north is 0 degrees, due east is 90 degrees, due south is 180 degrees, and due west is 270 degrees.
