Alien civilizations - Topic Home
Alien civilizations - Link Updates List
Universe Has Probably Hosted Many Alien Civilizations: Study | Space
https://www.space.com/32793-intelligent-alien-l...
How many alien civilizations are out there? A new galactic survey holds a clue.
https://www.nationalgeographic.com/science/arti...
The Milky Way is full of habitable real estate, with roughly half of all sunlike stars...