Why would any rational person believe science provides objective knowledge of reality?

Newton sat under the tree, and the apple fell on his head. You put a million people under a million trees, and dropped an apple right above them, all million would get knocked on the head (uming the aim of all the apples were true.) I agree one person alone cannot make one observation and call it a scientific fact. But when millions of people all witness the same event, then its safe to say that this event is universal fact.