I know that there are no gods.

[Zenith]

Since atoms do exist, as long as humans have existed we have been aware of things that have contained atoms, so in that sense we've always been aware of atoms

that's the same as saying that people have always been aware of bacteria and viruses, because they have been ill since the beginning. BUT they didn't know it was micro-organisms there. So they were aware that there were no micro-organisms causing the diseases, by blaming others as causes, so their 'awareness' was wrong.