All models are incorrect, but some are useful.
Fine, you win Timon3, earth is not a blackbody because blackbodies don't actually exist.
Fine, you win Timon3, earth is not a blackbody because blackbodies don't actually exist.
It's fine to say "the earth behaves similarly to a black-body" or "a black-body is a good approximation for the earth". But that's different from "the earth is a black-body".