| They're not from around here, briefly | 41 |
| They're found at Area 51, supposedly | 40 |
| They're encountered in close encounters | 43 |
| They're certainly not from around here | 42 |
| They travel a long way to get here | 34 |
| They make contact in "Contact" | 40 |
| Theoretical foreigners, briefly | 31 |
| The Solomons on "3rd Rock From the Sun," e.g. | 55 |
| The invaders in "The Invaders" | 40 |
| The "gods" in "Chariots of the Gods?," in brief | 67 |
| Supposed makers of crop circles | 31 |
| Supposed crop circle makers, for short | 38 |
| Supposed crop circle makers | 27 |
| Superman and Supergirl, briefly | 31 |
| Subjects of an as-yet-fruitless search, briefly | 47 |
| Spacemen, for short | 19 |
| Space visitors, briefly | 23 |
| Space aliens | 12 |
| Some Wells creations | 20 |
| Some warriors in "War of the Worlds" | 46 |
| Some Trekkie costumes | 21 |
| Some sci-fi pilots | 18 |
| Some sci-fi navigators | 22 |
| Some say they live among us, briefly | 36 |
| Some say they live among us | 27 |
| Some cosplayers, for short | 26 |
| Some cosplayers at a Star Trek convention, for short | 52 |
| Some cosplay costumes | 21 |
| Some characters in "The X Files," for short | 53 |
| Some alleged abductors | 22 |
| Some aliens, familiarly | 23 |
| Some abductors, in stories | 26 |
| Some "X-Files" roles | 30 |
| Some "Stargate SG-1" characters, in brief | 51 |
| Some "Star Trek" convention costumes | 46 |
| Some "Space Patrol" chars. | 36 |
| Some "Space Patrol" characters, for short | 51 |
| Some "Men in Black" characters, for short | 51 |
| So-far-undiscovered ones, briefly | 33 |
| Sightings, briefly | 18 |
| Short tabloid subjects | 22 |
| Score keeper, for short? | 24 |
| Sci-fi villains, for short | 26 |
| Sci-fi subjects, for short | 26 |
| Sci-fi regulars | 15 |
| Sci-fi invaders, for short | 26 |
| Sci-fi extras | 13 |
| Sci-fi creations | 16 |
| Sci-fi characters: Abbr. | 24 |
| Sci-fi characters, for short | 28 |
| Sci-fi beings, for short | 24 |
| Saucerful? | 10 |
| Saucer occupants, in brief | 26 |
| Saucer occupants, for short | 27 |
| Saucer contents, in brief? | 26 |
| Saucer contents, in brief | 25 |
| Saucer contents, for short? | 27 |
| Saucer contents, for short | 26 |
| SAT developer | 13 |
| SAT corp. | 9 |
| SAT administration gp. | 22 |
| SAT administerer | 16 |
| S.A.T. administrators | 21 |
| S.A.T. administrator | 20 |
| Roswell, N.M. visitors? | 23 |
| Roswell visitors, for short? | 28 |
| Roswell crashers, purportedly | 29 |
| Roswell crashers, in brief | 26 |
| Romulans, e.g. | 14 |
| Predators in the "Predator" films, for short | 54 |
| Possible UFO pilots | 19 |
| Popular 80's dolls | 22 |
| Outworlders of fiction | 22 |
| Otherworldly visitors, for short | 32 |
| Otherworldly ones, for short | 28 |
| Otherworldly beings, for short | 30 |
| Org. that produces college entrance exams | 41 |
| Org. that administers PSATs and GREs | 36 |
| Ones from far away | 18 |
| Non-earthlings, briefly | 23 |
| Neptunians and others | 21 |
| Natives of Minbar on "Babylon 5," e.g. | 48 |
| Movie alien et al. | 18 |
| Most of the characters in "The Hitchhiker's Guide to the Galaxy" | 78 |
| Mork and Alf, e.g. | 18 |
| Mork and Alf | 12 |
| Men from Mars and women from Venus | 34 |
| Martians, for short | 19 |
| Martians, e.g., for short | 25 |
| Martians and Venusians, for short | 33 |
| Martians | 8 |
| Many "Star Trek" extras, for short | 44 |
| Many "Star Trek" characters, briefly | 46 |
| Many "Star Trek" characters | 37 |
| Many "Futurama" characters, briefly | 45 |
| Long-distance travelers, in theory | 34 |
| Little green men: Abbr. | 23 |
| Letters for college-bound students | 34 |
| Legendary abductors | 19 |
| Latin connectors | 16 |