PPT-Galaxies - Chapter

23 vs 1 First spiral nebula found in 1845 by the Earl of Rosse Speculated it was beyond our Galaxy 1920 Great Debate between Shapley and Curtis on whether spiral nebulae were galaxies beyond our own Settled in 1924 when Edwin . Modern Cosmology. Look at your thumb.. The matter in it was present in the fiery beginning of the universe. . . Cosmology. , the study of the universe as a whole, can tell you where your matter came from and where it is going. . Except for nearby, we can only see bright galaxies. I will ignore dwarf . spheroidal. (. dSph. ) and dwarf elliptical (. dE. ) classifications. Galaxies . come in four broad categories, based on their appearance. Li Jiang-Tao. 1. Service d’Astrophysique, CEA, Saclay, France. 2. . Department. of . Astronomy. , . University. of Michigan, Ann Arbor, USA. Outline. 1. Introduction. 2. Diffuse X-ray . observation. So far we have talked about “small” things like stars, nebulae and star clusters. Now it’s time to get big!. What are the “Spiral Nebulae”?. The Shapley – Curtis Debate. April . 1920. Harlow Shapley…The Milky Way . Galaxies . And the Foundation of Modern Cosmology. How are the lives of galaxies connected with the history of the universe?. Hubble Deep Field. Our deepest images of the universe show a great variety of galaxies, some of them billions of light-years away. Giuseppina. . Battaglia. Instituto. de . Astrofisica. de Canarias, Tenerife. Credit. : ESO/. H.H.Heyer. Credit. : ESO/L. . Calçada. Karachentsev. et al. 2014. Individual . Red . Giant Branch . stars. Craig Sarazin. University of Virginia. M86. (. Randall et al. 2008). . Abell. 2052. (Blanton et . al. . 2011). Optical light dominated by bulge. Last star formation typically billions of years ago. around Abell 370, . a galaxy cluster at z = 0.37. International SKA . Forum 2010 . Philip Lah. A New Golden Age for Radio Astronomy. Collaborators:. . Frank Briggs (ANU). . Michael Pracy . Let’s look back at the rotational velocity equation:. v = (M. interior. G/r). 0.5. The rotational velocity is constant at big r values.. What must we conclude?. The mass interior to the orbit is still increasing. Even after the radius r has gone beyond the last of the stars. It must be increasing in order to hold v constant.. Islands of Stars. Our goals for learning. :. How are the lives of galaxies connected with the history of the universe?. What are the three major types of galaxies?. How are galaxies grouped together?. .. 1. First spiral nebula found in 1845 by the Earl of . Rosse. . Speculated it was beyond our Galaxy.. 1920 - "Great Debate" between Shapley and Curtis on whether spiral nebulae were galaxies beyond our own. Settled in 1924 when Edwin . Priest Associate Professor of Physics. Galaxies. 9/4/18. Milky Way Galaxy Contents & Motions. 9/11/18. Milky Way Environment & the Local Group. 9/18/18. Other Galaxies & Clusters of Galaxies. The Hubble Deep Field. 10 day exposure –field located in the Big Dipper. Edwin Hubble. Edwin . Hubble. Hubble’s Galaxy Classification . Spiral Galaxies. galaxies like the Milky Way with arcing structures lying in a plane and emanating from the nuclear bulge. Laura . Magrini. INAF- . Osservatorio. . Astrofisico. di . Arcetri. In Our Galaxy. Open clusters (disc population): . Many (~2200 known clusters). . even more new candidates in the inner disc from infrared surveys .