Planets?

Where does the assumption come from that asserts that Earth is necessarily similar to these planets?

from photographic data

Let me rephrase: Where in FE does the assumption come from that asserts that Earth is necessarily similar to these planets?

The original poster asked for what FE's beliefs are, and "photographic evidence" is only believed by RE.

Let me rephrase: Where in FE does the assumption come from that asserts that Earth is necessarily similar to these planets?

The original poster asked for what FE's beliefs are, and "photographic evidence" is only believed by RE.

Correct, they must conisder the whole theory, not individual parts of it. Throwing in an RE belief is essentially setting up a strawman.