Editing Openai/6946e998-79f0-8007-9a65-19828450838d (section)

=== No, η⊕ does not implicitly assume Venus or Mars are unsuitable. ===
It does not treat them as mistakes.
It simply counts planets with fluxes similar to what an “idealized Earth-like atmosphere” could tolerate.

Because Venus and Mars both fall within the optimistic habitable-zone flux limits, a naive η⊕ count would treat them the same as Earth.

Which is why η⊕ is best understood as:

“How many Earth-size planets are in Earth-like lighting?”

—not “How many are Earth-like?”