Which Angel caused the Second Impact?

Known only to a select few was that the meteorite impact story was simply a cover up: the true cause of Second Impact was when the First Angel, Adam, exploded as the result of a “Contact Experiment” carried out by the Katsuragi Expedition, which was itself secretly backed by the mysterious Seele organization.

What caused the first impact?

First Impact (also known as the “Giant Impact”) is an Impact which occurred in prehistoric times when the Black Moon, a giant spherical object, collided with the Earth in what is now the Hakone region of Japan. The collision caused an explosion that launched a massive amount of material from Earth into orbit.