All that talk about extraordinary claims requiring extraordinary evidence—or otherwise—misses the point. There is no evidence for either:
A recent profile in Astronomy focused on Abraham Loeb (pictured) a Harvard astronomer who is convinced that closed minds are a key barrier to our finding extraterrestrials. Statistically, he thinks, they must be out there somewhere: …
A prolific thinker, he has, along with collaborators, come up with a number of new ideas about where and how to look, and what to look for. For example, he thinks, based on astronomical calculations, that life is more likely to evolve in the distant future than now. He also uses intriguing forensic approaches to the search for extraterrestrialsNews, “Why do people who believe in extraterrestrials dismiss ghosts?” at Mind Matters News
Sure, but none of it has panned out. ETs perform no better than ghosts in the evidence department.
That said, people who have a fully naturalist worldview can believe that there are extraterrestrials but not ghosts. That’s worldview, not evidence as such.
See also: Tales of an invented god