Evidence Surviving the Cleanup Operation

Although the physical evidence was destroyed, photographic, video, and eyewitness evidence survives.

This evidence shows:

• Dust and fragments were ejected from the towers at high velocities.
• The tops of the towers exploded into descending mushrooming clouds of dust.
• The mushrooming dust clouds remained centered as they devoured the towers.
• The dust clouds grew to volumes several times the buildings' volumes, and covered Lower Manhattan with dust.
• The non-metallic components of the towers and their contents were pulverized to sub-100-micron dust.
• The steel superstructures were shredded.
• Intense heat in the basements melted the foundations of the core columns.