Here's an old favorite of mine. The Martian Chronicles by Ray Bradbury, who also wrote Fahrenheit 451. A lovely piece of old SciFi from back when we though Mars was inhabitable. It sort of imagines that the colonization of Mars would mirror the Westward Expansion of America. A fascinating read that really leaves you thinking once it's over. It also tells a lot about the time period in which it was written. The hopes and fears of that time ring throughout.