Astro Chapter 21 Section 1 Looking Back through time Galaxy evolution – study how galaxies form and develop Hubble can’t see back before 1-2 billion years James Webb space telescope – 2013 How did Galaxy form-H and He gas filled all of space uniformly when universe young-Matter was not perfectly uniform-Certain region denser than others-Denser region = slower expansion due to pulls-In a billion years, expansion of these dense regions halted and reversed and material began to contract into protogalactic clouds-This formed galaxies-In spiral galaxy, first generation stars grew from densest coldest clumps of gas
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This note was uploaded on 12/13/2008 for the course ASTRO 1101 taught by Professor Lloyd,j during the Fall '07 term at Cornell.