Andromeda Script Slide 1 • The Andromeda Galaxy (also known as M31) is an ordinary spiral galaxy approximately 2.5 million light-years away in the constellation Andromeda. • http://en.wikipedia.org/wiki/Andromeda_Galaxy Slide 2 • According to Robert Burnham, Jr. "The first hint of the true nature of the Andromeda Galaxy came late in 1923 when several stars were identified in the system [by Edwin Powell Hubble] who thus definitively established the great spiral as an extra-galactic object • http://www.solstation.com/x-objects/andromeda.htm Slide 3 • The Andromeda Galaxy is easily visible to the naked eye in a moderately dark sky; however, such a sky is available only in smaller towns and isolated areas reasonably far from population centers and sources of light pollution. It appears quite small to the eye because only the central part is bright enough to be visible, but the full angular diameter of the galaxy is seven times that of the full moon • http://en.wikipedia.org/wiki/Andromeda_Galaxy Slide 4 • Andromeda has bright yellow nucleus, dark winding dust lanes, gorgeous blue spiral arms and star clusters Andromeda's visible mass may total around 300 to 400 billion Solar-masses • http://antwrp.gsfc.nasa.gov/apod/ap051222.html • http://www.solstation.com/x-objects/andromeda.htm Slide 5 • Andromeda has a nucleus with a double structure. The "nuclear hot-spots" are located close together, considering that the galaxy's spiral disk has been estimated to be anywhere from 150,000 to more than 200,000 ly across while the observed central area measures only around 30 ly wide. Subsequent ground-based observations led some astronomers to speculate that two galactic nuclei do indeed exist, are moving with respect to each other, and that one nucleus is slowly disrupting the other through tidal forces • http://www.solstation.com/x-objects/andromeda.htm Slide 6 • Andromeda's core has a supermassive central black hole of around 140 million Solar-masses • http://www.solstation.com/x
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