Most UFO's are things that are misconcepted by unknowing spectators. they mistake flights of birds, planes,... for spacecraft. 99,99% can be proven by checking date, time,... by a professional institution. Don't forget the confessions of hoaxes either.
Science can prove pretty much nowadays but I still think there will be a certain border we'll reach one day.
Perhaps we'll find the
Origin of
Universe etc. But I doubt we'll ever traval at the speed of light or create a costum- made human or even
Stretch the length of human life (150+ years average)