 Another article in "Science" reported evidence of nanodiamonds in a geological deposit thought to correspond to the event.In the same issue, another article reported that the nanodiamonds were evidence for carbonaceous chondrites or comets at the start of Younger Dryas whose airbursts and surface impacts caused widespread damage.A special debate-style session was convened at the 2009 AGU Fall Meeting in which skeptics and supporters alternated in giving presentations.