QQC Part Two

"Under Drake's equation you divide the number of stars in a selected portion of the universe by the number of stars that are likely to have planetary systems; divide that by the number of planetary systems that could theoretically support life; divide that by the number on which life, having arisen, advances to a state of intelligence; and so on."

This quote to me is quite strange. It is describing a theoretical formula to calculate the chances of life in the cosmos. This equation boggles me for many reasons; the main point that I have trouble with is how to you find out any one of the variables. How do find the number of systems that could theoretically support life if we can't visit them or even get close to them to see? How do we know how many planets have life and if they have arisen to a 'state of intelligence,'? If we have no answers for any of these probabilities then what good does this formula do for science?

Atoms

QQC

"Atoms are so numerous and necessary that we easily overlook that they needn't actually exist at all."

This quote raises so many question's for me; why aren't they needed, why do we have so many, how is there enough atoms to fill this universe, and why is there no law that governs why atoms are here? Yes we need atoms to create everything in our physical world, but why are they made the way they are? Why are atoms structured in such a way as to be able to create physical masses? Something that I find interesting is that even though they fill our universe, you can't see every single one. One question that just popped into my mind was, does anyone actually know how many atoms there are in the known universe?