We use what we know about Earthits structure, atmosphere, geologic activities, and processesto prove or disprove our theories of other planets.

We use what we know about Earth—its structure, atmosphere, geologic activities, and processes—to prove or disprove our theories of other planets. Describe one such example of our use of Earth analogs to determine the circumstances elsewhere, and explain how it might influence our explorations in the future. And for the last time this term, don’t choose an example that already has been posted.