[Blackmane]

We assume that the 7 days to create the Earth were 7 Earth days, but there is no way to determine if a day to God is actually a day to us or a thousand years.

Since we can have no definitive answer to that question, we can only assume that it was not done in 7 Earth days and that depends on the suns orbit of the earth. Since light was not created until day 2 (or 3), that already is pretty good evidence supporting a non-Earth day.