T Mark Hightower

Review of "The Ground Zero Model" by Heinz Pommer and Colleagues Reviewed by T. Mark Hightower Retired NASA engineer NYC 911 WTC Twin Tower and Building 7 Nuclear method of destruction Clearly Explained The Ground Zero Model by Heinz Pommer and Colleagues presents a compelling model for how underground nuclear devices of very high energy were likely used to bring down the Twin Towers and Building 7, explaining very well much of what was observed in their destruction. Calling their explanation a model is very much in keeping with the scientific method when one is seeking to explain observations without knowledge of exactly how the deed was carried out. When I was on Jim Fetzer's show The Real Deal on July 06, 2011 I presented rough calculations for how much conventional high explosives would have been needed to bring the Twin Towers down by just severing the load bearing members. I did not attempt to calculate or estimate what additional quantity of explosives would have been needed to account for the high degree of comminution or pulverization observed. The calculated result was on the order of hundreds of tons of TNT for each Twin Tower. When information estimating the quantity of iron rich spheres produced by the Twin Tower destruction was considered, on August 25th 2011 in a blog post I presented a calculation that if the iron rich spheres came from steel, heating and melting it, that this energy alone would have accounted for multiple kilotons of TNT energy equivalent for each Twin Tower. But here again this is not including what energy was needed to accomplish the large degree of pulverization of most of the building materials and contents of the buildings. I was open to the possibility that nuclear devices could have been used but exactly how seemed impossible to narrow down. If such nuclear devices existed they would have been used, I thought, because they would be more effective and efficient than conventional explosives. I did continue to follow presentations of those presenting nuclear hypotheses to some extent through the years but I was usually feeling the explanations were too far beyond my areas of expertise to fully understand and fairly judge. Reading The Ground Zero Model is the first time I feel a nuclear model comes closest to explaining the observable facts, and the researchers have done a good job of making it mostly understandable to me at my level of nuclear expertise, having taken just one course in nuclear engineering as an undergraduate, but never really working in that field during my career. I would like to see others with different hypotheses present their models to the same degree of clarity that these researchers have done with The Ground Zero Model. They have set the bar very high indeed. The most significant aspects to me of The Ground Zero Model are the underground nuclear device not violently exploding like a nuclear bomb but burning slowly or deflagrating more like a nuclear powered rocket engine or a nuclear Roman candle, and the tremendously high energy 150 kiloton estimate for each Twin Tower. I look forward to following up and studying all of the many links that are in The Ground Zero Model book. I am particularly interested in learning how much of the 150 kilotons went into waste heat to the environment including the heat that continued to be produced by nuclear reactions that continued for many months underground and in the pile after the initial destruction of that day.