Lecture 5: Mapping Earth and Sky
Where are we? Where is someplace else? How do I get from here to\nthere? These are questions we need to answer both on the Earth and in\nthe Sky to assign a location to a place or celestial object on the\nsurface of a sphere. We start by introducing angular units, and use\nthem to describe the terrestrial system of latitude and longitude on the\nspherical Earth. We then define the Celestial Sphere, with its\nCelestial Equator and Poles, and begin to define an analogous coordinate\nsystem on the sky. An important wrinkle is that what part of the sky we\nsee at any given time depends on both where we are on the Earth, and\nwhat date/time it is. This gives us the start of the coordinate system\nwe need to begin our exploration of motions in the sky in the next\nlectures. Recorded 2006 Sep 26 in 100 Stillman Hall on the Columbus\ncampus of The Ohio State University.