What evidence exists for the existence of aliens?

There is currently no concrete evidence for the existence of aliens, however, there are several factors that suggest the possibility of extraterrestrial life. Some scientists point to the sheer size of the universe, which contains billions of galaxies with billions of stars, as evidence that there must be other forms of life out there. Additionally, several high-profile sightings and alleged encounters with UFOs have been reported over the years, although none have been substantiated. Finally, the discovery of microbial life on Mars or other planets within our own solar system would greatly increase the likelihood of intelligent life existing elsewhere in the universe.

This mind map was published on 12 June 2023 and has been viewed 125 times.