For most meteor impacts, the meteor itself completely vaporizes and doesn't deposit any solid chunks into the target. This is why moon craters are almost always

For most meteor impacts, the meteor itself completely vaporizes and doesn't deposit any solid chunks into the target. This is why moon craters are almost always circular despite the impacts occurring at all angles of incidence. It seems the implication here is that the limit where the masses are comparable plays out very differently. Seems like it should be possible to estimate the hypothetical collion energy from the size of intact chunks.