PHYS 284 Lecture Notes - Lecture 9: Celestial Coordinate System, Celestial Equator, Lunar Phase
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Astr 138 fall 2017 exam 2 10/19/2017. Wien"s law: max = c / t, where c = 2,900 in units of (micrometers*kelvins degrees) Newton"s universal law of gravitation: force of gravity = g m1 m2 / r2: an observer vacations in cuba on the 21 north latitude line and goes star gazing. How many degrees above the horizon is the north star? a) It is not visible; it is below the horizon: 23. 5 , 69 , 0 , 21 , an observer is located in s o paulo, brazil, at -23. 5 (south) latitude. Can the observer see the north celestial pole: yes, no, sometimes, the same brazilian observer plants a vertical pole and watches the shadow cast by the sun over the course of a year. When does the pole cast no shadow at noon: never. Infrared light: x rays, visible light, microwaves, which wavelength regime contains potentially ionizing photons, microwave b)