When it comes to cosmological understanding, modern scientists are just interpretating the observations and as long as there is NO universal consensus of cosmos, mine and yours guesses are just as good.
You think. So the ancients were aware the cosmos contained stars like our own sun, planets, they were aware and had measured the temperature differences of the CMB, how about the Planck epoch in the history of the universe?
There is considerable consensus in cosmology. However it does get fuzzy once you hit that Planck epoch