Much of the academic community assume that a typical catastrophic impact event consists of a single, large bolide. When asked what he thought of the possibility of a cluster impact event of smaller fragments, NASA’s David Morrison expressed doubt. He said he thought such an event would be “highly unlikely”. And since he’s the senior scientist at the NASA Ames Research Center, his views are representative of mainstream planetary science.
But ongoing inventories of the objects orbiting in the Taurid complex are bringing data to light that indicates that, in fact, the last extinction level impact event in the northern hemisphere was probably the work of a very large cluster of debris from a large disintegrating comet, not the kinetic impact of a single, solid bolide.
And in a 2009 paper by W.M. Napier, and titled Comets, Catastrophes, and Earth’s History we read ,
“The evidence that an exceptionally large (50-100 km) comet entered a short-period, Earth- crossing orbit during the upper Paleolithic, and underwent a series of disintegrations, now seems compelling. The idea is not new, but it has been strengthened by an accumulation of evidence from radar studies of the interplanetary environment, from the LDEF experiment, from numerical simulations of the Taurid complex meteoroids and ‘asteroids’, and from the latter’s highly significant orbital clustering around Comet Encke.
The disintegration of this massive Taurid Complex progenitor over some tens of thousands of years would yield meteoroid swarms which could easily lead to brief, catastrophic episodes of multiple bombardment by sub-kilometer bolides, and it is tempting to see the event at ~12,900 BP as an instance of this. Whether it actually happened is a matter for Earth scientists, but from the astronomical point of view a meteoroid swarm is a much more probable event than a 4 km comet collision.”
If Professor Napier is correct, we should expect to find the planetary scarring of a geologically recent super cluster impact event of smaller fragments somewhere in North America.
And in the world according to Google Earth, that planetary scarring does indeed exist. And a good case can be made that New Mexico, and West Texas, were a couple of the major impact zones. But in spite of posting pictures of these ‘enigmatic depressions’ for a couple of years now, none of the mainstream scientists I’ve written to seems to be interested in talking about them. And I haven’t been able to find evidence that anyone has done any real science at any of them either.
I struggle with the mystery of how they can be so dramatically obvious in satellite imagery, and yet, no one has gotten curious about them.
Their existence plays hell with the idea that we can estimate the age of a planetary surface by the number of craters we can see in a satellite image.
Even if they can be proven to have formed by something besides an impact event, we still have a problem. In satellite images they are visually indistinguishable from impact craters. If such geologic features can be shown to have a non-impact origin here on Earth, then what does that say for the very same geomorphology elsewhere in the solar system? Or the idea that you can estimate the age of a planetary surface by counting them?
Which would have the most profound effect on planetary science?
A series of large crater fields in North America describing the simultaneous impacts of thousands of small comet fragments, with thousands of sports stadium sized craters all the same late Pleistocene age?
Or proof that there is an active geologic process at work in the solar system that can produce thousands of circular depressions with raised rims, that are visually identical to impact craters?
If they are indeed impact craters, then they have a very profound effect on impact threat assessment. And they represent the cusp of a major paradigm shift in impact research. As we move away from thinking of a catastrophic impact event as being the result of the kinetic impact of a single solid body, to thinking of multiple fragment impact storms of mostly air-bursting smaller fragments.
Are they only sinkholes? Personally, I doubt it. Because if they are, and if any given sinkhole is only part of a larger cave system beneath, then they represent the surface manifestations of a giant, interconnected, cave system stretching across two states, and covering tens of thousands of square miles. It would have be the largest known cave system on Earth. And again, they are visually indistinguishable from impact craters.
If they weren’t formed by impact, then we can no longer assume that identical looking geologic features on the moon, and Mars, were formed by impact either, until we have been there ‘on the ground’.
No one’s talking about them yet. But that doesn’t mean I can’t keep pointing at them.
Here’s a few more.
The map coordinates, view height, and scale, are in the info bar at the bottom of each image.
If you’d like to see more, I’ve put a few other places in a photo gallery called Crater Field