I realize talking about aliens and UFOs can easily brand someone a kook, but there are now so many videos and observations from reputable people that the US military and US government openly admit there are things flying around our military bases that are technologically centuries (if not millennia) beyond anything we have or can even understand. Senator Marco Rubio has given interviews on this very subject and said just that, and a number of government officials and reports have been made on this subject.
Apparently US intelligence has many, many videos of these things that they're not releasing, or at least haven't yet, and the ones that have been declassified (after being leaked) are some of the LEAST compelling videos we have.
While nobody really knows wth these things are, we've reached a point where it's safe to say they're not of human origin. Whether we will ever know is unknown, but it's pretty wild, exciting, and terrifying nonetheless.