Life on other planets Vie extraterrestre 654 Human-alien encounters 396 Space warfare 270 Extraterrestrial beings 239 Science fiction 224 Exobiology 222 more ... PRO Adams, Mark B. (donor) (Adams Collection copy) 200 Interplanetary voyages 171 Science fiction, American 157 Space colonies 152 Extraterrestrial anthropology 147 Origin 141 Life 140 Good and evil 138 Exploration 131 Interstellar communication 116 Imaginary wars and battles 90 Unidentified flying objects 79 Astronomy 72 Exobiologie 71 Cosmology 66 Space ships 64 Planets 61 Robots 59 SCIENCE 56 Star Wars fiction 56 Space flight 55 Extraterrestres 53 Evolution 51 less ...