A Clearer View of the Spire's Demise
PAX-NBC Video of the North Tower Collapse
Click above for MPEG version of clip, here for AVI.
The image above shows what I have referred to as the spire, a remnant of the core of the North Tower that remained standing for about fifteen seconds after the collapse. This clip was part of a PAX/NBC compilation of views of the North Tower collapse, and is shot from east and a bit north of the tower, with the Woolworth Building in the foreground. The emergence and subsequent collapse of this peculiar remnant of the core is discussed in more detail in my first article about this object:: The Strange Collapse of the "Spire".
Near the beginning of the PAX/NBC compilation above, there are about ten seconds of footage from the same camera taken just as the collapse began. The image below is from the beginning of that footage.
(click to view video)
After the upper portion of the tower has disappeared into the dust cloud the footage is intercut with a telephoto view from the north, and we do not return to this camera angle until the spire is about to collapse. Here is an interesting WMV clip of the formation of the spire from another vantage point to help bridge the gap. And another interesting Quicktime video showing the north tower collapse from the northeast, with the spire becoming visible at the very end.
The picture below is the first frame following the missing footage of the emergence of the spire, and catches it at the end of its fifteen seconds of stability. Notice that the stubs of broken-off cross braces can still be seen along the single column at the top of the structure.
Here is a close-up of the top of the spire just after it became visible that shows these in better relief, cropped from a still photo found at Here Is New York:
Immediately after this the spire begins to fall straight down along its own axis, at least initially without any change in appearance. But at about the point when its top is even with the tapering roof of the Woolworth Building a distinct change takes place.
All at once the outline of the previously solid looking steel columns begins to become less well defined. Very soon after this it is clear that the steel columns have turned into a fine powder, though remaining in a narrow vertical column somewhat wider than the original outline. The heavier portion of the dust settles straight down fairly quickly, leaving only an insubstantial wisp of lighter dust that drifts off to the left. It has been suggested that this was simply dust that had been somehow clinging to the columns, but it would be difficult to explain how any amount of dust could cling to the vertical sides of the columns after being scoured by the turbulent cloud from which it emerged. And in any case it is clear from this footage that the sharp outline of the original columns is completely lost well before they reach the bottom of the screen.
Because this video was taken with a tripod-mounted camera located close to the collapse the image is sharper than the other known footage of the event (seen here). There can be no doubt that the cluster of steel box columns comprising the spire, after surviving the violence of the collapse itself, did in fact disintegrate almost at the moment that it began to fall. I cannot begin to speculate on the kind of technology needed to make this happen, but can say with some certainty that even conventional explosives would not create such a disintegration, and nothing that could happen in a gravitational collapse would resemble this.