My good friend Ian Juby has developed a fantastic series on YouTube discussing the phenomenon of UFOs. I am linking it below. There are 4 parts. The below link is all of them or you can subscribe to his YouTube channel and easily get them all.
These answer pretty much any question you may have including how many of these UFOs are likely real and even close encounter phenomena with extra terrestrials.
Enjoy and listen well. I also suggest you give him a gift or choose to support him regularly. He is a tireless advancer of the truth of Gods word and absolutely hilarious to boot!