Newton’s Firmament

"And therefore as it is possible, that in the remote regions of the fixed stars, or perhaps far beyond them, there may be some body absolutely at rest; but impossible to know..." Sir Isaac Newton speculating about the firmament.

Elliptical vs. Cardioid

We need to know that some concepts are paradigm-dependent. This means that they only apply after accepting the premise of a paradigm. We've been discussing elliptical planetary orbits, that's a heliocentric concept.