ASTRO 103 Chapter Notes - Chapter 0: Northern Hemisphere, Solar Eclipse, Dayside
Document Summary
Umbra: the dark central part of the shadow. Penumbra: the outer, lighter part of the shadow. Eclipse: occurs when on celesial body is between the sun and another celesial body. Type depends on where the observer is located and on the relaive sizes of the various bodies. Solar eclipse: when the moon comes between is and the sun. Someimes closer to the sun than the average distance (sun looks slightly bigger) and the moon is someimes farther from the earth than it"s average distance (moon looks slightly smaller). Total eclipse - umbra of moon"s shadow on earth is very small. B: umbra doesn"t reach all the way to earth. Observer near point of shadow would see annular eclipse. Illustraion of shadow of moon on earth during total solar eclipse. Solar eclipse viewed from any spot on earth is a very brief phenomenon. Long eclipse = totality lasts 3-4 minutes from best locaion.