My thoughts too, if it was mostly vaporized (in cloud form) then why is there a big 'ol hole in the ground? and the article did not really explain what happened to the iron either, seems like they would have found more.....
Studies like this are so pitifully stupid!
Sometimes there are no explanations for phenomenom like this.
Man, (the species) in general wants to say they understand everything in the world.
Somehow........it's just not that important.
Tax dollars are used for this group, I would imagine.(rolling my eyes)