I was learning about the formation of Earth on Kahn Academy where it was mentioned that a protoplanet named Theia had a glancing impact with the earth and formed the moon. It seems like there is also newer research (Read on Wiki) that suggests it was a head on collision. I'm curious if there is a current scientific consensus on this.
My understanding of this event is that a more direct hit is possible due to the identical nature of Earth and moon Oxygen isotopes. Suggesting a vigorous mixing and high-angular-momentum impact. Meanwhile, this article suggests otherwise "The most favorable conditions for producing a sufficiently massive and iron-depleted protolunar disk involve collisions with an impact angle near 45 degrees and an impactor velocity at infinity <4 km/sec." I'm assuming that if the protolunar disk was lacking iron it means the hit would not have exposed the interiors of either protoplanet in the collision and would have been more of a glancing blow.