THE UNIVERSE MAY NOT BE A NICE NEIGHBORHOOD . . . “The oldest and strongest kind of fear is fear of the unknown,” the grand master of horror, H.P. Lovecraft, once wrote. And the greatest unknown is the vast universe, shrouded in eternal cosmic night. What things might be on other planets—or in the dark gulfs between the stars?  Giving very unsettling answers to that question are such writers as Ray Bradbury, Arthur C. Clarke, Robert Sheckley, Philip K. Dick, James. H. Schmitz, Clark Ashton Smith, Cyril M. Kornbluth, Alastair Reynolds, Neal Asher, Sarah A. Hoyt, and more, all equally masters of science fiction and of terror.  One might hope that in the void beyond the...