Human-alien encounters 106 Extraterrestrial beings 34 Interplanetary voyages 18 Life on other planets 17 Exploration 13 Seres extraterrestres 11 Video recordings for the hearing impaired 8 Mais ... Space ships 7 Space warfare 7 Time travel 7 Space flight 6 Encuentros humanos con extraterrestres 5 Fathers and sons 5 Friendship 5 Men in black (UFO phenomenon) 5 Closed caption video recordings 4 DNA damage 4 Enemies 4 Government investigators 4 Government policy 4 Informers 4 Manned space flight 4 Mercenary troops 4 Refugees 4 Relocation (Housing) 4 Science fiction films 4 Virus-vector relationships 4 Bounty hunters 3 Drama 3 Exploration of outer space 3 menos ...