【Abstract】In the morning between 6 ~ 7am of April 4, 2017 , a sarin chemical attack took place in Khan Shaykhun in the Idlib Governorate of Syria. It killed 86 people and injured more than 500. On the morning of 7 April 2017, 72 hours after the attack, the Trump Administration of the United States launched 59 Tomahawk cruise missiles from the USS Porter on Shayrat Airbase, as a "punishments" and a strong admonition.

The only undisputable fact is that the sarin attack did take place. But the Syrian Government vehemently denied that it  carried out the attack. Videos have been posted on the Internet alleging that a crater on the street of Khan Shaykhun was the scene where a chemical was dropped, causing the casualties. However, there are many inconsistencies about the crater and the debris that suggest the scene was staged and evidences were tampered. Dr. Theodore Postol, a top world weapon expert, has hypothesized some setup of munitions that may have caused the crater and the debris as shown in the videos.

As the crater and the debris are the only available evidences, in this talk, we use the computer modeling tool of LS-DYNA to study and analyze them for forensics. The explosion model in LS-DYNA is the Jones-Wilkins-Lee (JWL-) Equation of State. This equation is to be coupled with the conservation of mass, momentum, energy and constitutive equations for the numerical computation and simulation of the explosion and fracture effects. We will indicate how to proceed with the computation with LS-DYNA and the input, and also how to do data validation. Supercomputer results the outputs are then visualized through several videos. Based on the videos, discussions and assessments about the chemical attack are then made. This research work is still ongoing and unfinished. Some future outlook will be provided.