Complex sentence: Hadean eon, Azoic supra-era, and Cryptic era start as the Earth-Moon system forms, possibly as a result of a glancing collision between Proto-earth and the hypothetical protoplanet Theia (see giant impact hypothesis).
Split into simpler sentences: Hadean eon, Azoic supra-era, and Cryptic era start. The Earth-Moon system forms, possibly as a result of a glancing collision between Proto-earth and the hypothetical protoplanet Theia (see giant impact hypothesis).