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Appendix: Andromeda Facts Appendix: Andromeda Facts Andromeda Galaxy D. Schultz, The Andromeda Galaxy and the Rise of Modern Astronomy, 259 Astronomers’ Universe, DOI 10.1007/978-1-4614-3049-0, © Springer Science+Business Media New York 2012 260 Appendix: Andromeda Facts Milky Way Galaxy Andromeda galaxy (M31) Milky way galaxy Hubble type SB spiral SB or SC spiral Address and Largest member of local Smaller brother and relatives group of 30–40 galaxies member of local group of 30–40 galaxies Mass 3.2 × 10 11 suns 2 × 10 11 suns Diameter 220,000 light years 100,000 light years Number of stars 4 × 10 11 2 × 10 11 Age 4.6 billion years 4.6 billion years Rotational speed 220 km/s 250 km/s Red shift −300 km/s (moving NA toward earth) Number of globular 300 150 clusters Distance today 2.4 million light-years 0 (720 KPC) Distance in six 0 Andromeda and the billion years Milky Way collide and merge to form a super galaxy Time for one 225 million years 220 million years rotation References Allen RH (1963) Star names, their lore and meaning. 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Harper & Row, New York Kuhn TS (1957) The Copernican revolution: planetary astronomy in the devel- opment of western thought. Harvard University Press, Cambridge Lavalle J et al (2006) Indirect search for dark matter in M31 with the CELESTE experiment. Astron Astrophys 450:1–8 Leavitt H (1912) Periods of 25 variable stars in the small magellanic cloud. Harv Coll Obs 173:1–3 Livio M (2011) Lost in translation: mystery of the missing text solved. Nature 49:171–173 Lockyer JN (1964) The dawn of astronomy: a study of temple worship and mythology of the ancient Egyptians. MIT Press, Cambridge Lovejoy AO (1964) The great chain of being. Harvard University Press, Cambridge Lundmark K (1924) The determination of curvature of space-time in de Sitter’s world. Mon Not Roy Astron Soc 84:747–770 MacPherson H (1919) The problem of island universes. Observatory 42:329–334 McVittie GC (1937) The distribution of extra-galactic nebulae. 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Lowell Obs Bull 2:56 Spinrad H (2005) Galaxy format and evolution. Praxis, Chichester Stebbins J, Whitford AE (1934) The diameter of Andromeda nebula. Proc Natl Acad Sci 20:93–98 Tannenbaum DG, Schultz D (1998) Inventors of ideas: an introduction to western political philosophy. St. Martin’s Press, New York References 265 Van Maanen A (1935) Internal motions of spiral nebulae. Astrophys J 81:336 Williams RC, Hiltner WA (1941) Dimensions and shape of the Andromeda nebula. Pub Obs Univ Mich 8:103–106 Wilson HC (1916) The light curve of T Andromedae. Ann Harv Coll Obs 80:135–145 Index A B Adams, J.C. , 21, 31, 89, 90, 182 Baade, W. , 180, 208–209, 211–212, 225, Age of the universe , 204 235, 237 Airy, G. , 90 Babylonian astronomy , 35, 39 Alfarabi , 27 Bacon, F.
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