Ben Levi,
I am not confusing anything. The amount of time between new moons had been correctly calculated before 120 BCE by the Greeks and as far back as 300 BCE by the Babylonians as I mentioned in my earlier comments. This is not based off of any religious text. It’s a fact.
I am not saying Chazal weren’t more knowledgable then the Average citizen in their time. Im sure they were very educated in the “science” of their time. The average citizen probably didn’t know anything.