Theia and Gaia
There’s a wild, but interesting, theory circulating amongst astrophysicists these days that the present Earth and its Moon are the result of a head-on collision between Earth and another “embryo planet” called Theia. You may already be familiar with the story as reported in the press. It’s weird because this was the theme of Lars von Trier’s depressing 2011 film Melancholia. It really is a time of wonders.
Intuitively, though, it just doesn’t “feel” right. Space is a pretty big place, and the head-on collision of two planets seems like a wildly improbable event. There is, though, another possible scenario to account for the similarities between the Moon and the Earth that, until I read about the collision of Theia and Gaia, I never really took all that seriously. It’s “Seth’s”, and in retrospect, it seems just as plausible.
According to Seth, this is not the first “Earth”. There was another “Earth, (Theia perhaps?) and like the present Earth it was inhabited. In their folly, the inhabitants of this other Earth destroyed their planet — obliterated it. Sound familiar? In any event, from the remnants of that destroyed world, our present Earth and its Moon were born.
That’s a pretty wild tale in itself, but there are some reasons why it might be more plausible than the theory of worlds in collision, or that the present Earth is actually a composite mixture of two planets.