Download Galactic Encounters by William Sheehan - mirror 1 --- mirror 2 --- mirror 3 -- --------------- br Synopsis: Written by William Sheehan, a noted historian of astronomy, and Christopher J. Conselice, a professional astronomer specializing in galaxies in the early universe, this book tells the story of how astronomers have pieced together what is known about the vast and complicated systems of stars and dust known as galaxies.brThe first galaxies appeared as violently disturbed exotic objects when the Universe was only a few 100 million years old.