The formation of the Moon from the debris of a slow and grazing giant impact of a Mars-sized impactor on the proto-Earth (Cameron & Ward 1976, Canup & Asphaug 2001) is widely accepted today. We present an alternative scenario with a hit-and-run collision (Asphaug 2010) with a fractionally increased impact velocity and a steeper impact angle.
Cite
@article{arxiv.1207.5224,
title = {A hit-and-run Giant Impact scenario},
author = {Andreas Reufer and Matthias M. M. Meier and Willy Benz and Rainer Wieler},
journal= {arXiv preprint arXiv:1207.5224},
year = {2015}
}