"What surprises me about the way science has progressed"

I would be very interested to find out where science came from and when it was created. Scientists say that the universe was created by the Big Bang theory and that the Earth has been spinning around the galaxy for 4.5 billion years, but how do they know this? Obviously no one would have been alive before the Earth had been created.

It is interesting as to how major scientific theories and ideas have evolved from the tiniest things. Take Dr Alexander Fleming for example - he created penicillin by accident from a contaminated bacterial culture in his laboratory.