https://www.vice.com/en_us/article/bvgyx5/the-next-generation-of-super-sensitive-alien-hunting-telescopes-is-coming

Humans have wondered whether we are alone in the universe for millennia, but the question has taken on new dimensions in recent decades with the discovery of thousands of exoplanets. These worlds, which have been observed since the 1990s, orbit other stars and suggest that the Milky Way is teeming with planets, some of which may be habitable or host alien life.

A clear detection of an alien civilization would be one of the most consequential discoveries in history, which is why the search for extraterrestrial intelligence (SETI) community has rigorous standards about what qualifies as evidence when looking for “technosignatures.”