RECONSTRUCTING THE HIAWATHA IMPACT

Reconstruction painting of the Hiawatha impact, watercolour on paper. Carl Christian Tofte 2016

Following the publication by Kurt H. Kjær et al. of their discovery of an asteroid impact crater in northern Greenland - an area now covered by the Hiawatha Glacier* - I have one secret less to keep. I now have the opportunity to reveal some details about the synergetic process it was to work closely together with the team of researchers in an effort to reconstruct the impact event.

An asteroid impact has never been observed, and visualizing it, which became my task, was by no means easy! Just putting a pencil to the paper rose lots of questions. 

First and foremost the scene of the event had to be determined - and what wast the picture supposed to show? A free brainstorm resulted in the following: The asteroid with a tail of fire through the atmosphere with smaller offshoots drawing trails of light - the latter, not least over Cape York, where the big iron meteorite now adorning the yard of the Geological Museum in Copenhagen was found. This same meteorite may well be a fragment of the very Hiawatha Asteroid, thus suggesting a plausible course of the asteroid, coming towards Inglefieldland from the southwest.
 
The working hypothesis (the confirmation of which will need further field research) was that the impact event occurred 12.000 years ago. By then, the Inland Ice covered not only Greenland but a large portion of the Baffin Bay, as well. It was also thicker and thus without nunatks. A ground level view from somewhere out in the Baffin Bay was suggested. In that way both Cape York and the face of the ice shelf towering over the sea would be visible. But then again, this would give a minimum distance of several hundred kilometers from the viewpoint to the point of impact. Next question; How large would the explosion caused by a heavenly iron body with a diameter of ca 1 km be? The answer is a fire ball with a 20 km diameter (or maybe rather half a fire ball). In other words an explosion covering the entire atmosphere, but not very big seen from several hundred kilometers distance. Accordingly, I had to move the viewpoint much closer, discarding Cape York, which was no big loss - 12000 years ago that area would in any case have been unrecognizable, covered as it was by several kilometers of ice.
We ended up with a scene showing an even, wind swept ice surface.

The next problem was the offshoots. First I was told that these would fly ahead of the asteroid because they were smaller and, supposedly, had less friction with the atmosphere. Fortunately this was corrected - the opposite is the case. I pictured these offshoots as occuring in outer space, entering the atmosphere as a swarm, as seen below:

Early sketch. Here the offshoots enter in all sorts of directions - this is all wrong!

All wrong! The offshoots occur only after the asteroid enters the atmosphere, and further they will radiate from the "tail" of the asteroid. To show any offshoots at all I would have to draw the impact explosion at a stage prior to being fully devolved. An explosion covering the entire height of the atmosphere would "swallow" any offshoot - only a ball of light would be visible. Or rather would theoretically be visible. My research included watching quite many films of nuclear explosions. The actual experience of watching the impact, would most likely be a total "white out" of blinding light. Thus the naturalistic approach would be a white sheet of paper, but as this is rather boring, I settled for painting what you would see, given that you would actually be able to see anything.
With all this in place, I drew the picture below.

Next step. Here the impact explosion is drawn in pencil in lateral view at a stage prior to being fully developed. The diameter of the explosion is here around 5 km.

I tried painting the pencil drawing, adding some clouds - but these totally dwarf the explosion! They are much too big, resulting in a William Blake-like scene of apocalyptic serenity!

One from the research team pointed out, that if this is a lateral view, all of the offshoots should be below the asteroids tail. Now it became necessary to make a really simple sketch of what was actually happening, as seen below:

Simple sketch of an asteroid, offshoots and their area of ground impact.

 Now, at least I, and supposedly several researchers, knew a lot more than we did by the time of the initial brainstorm. I was now ready for the final painting. To twist the scene from apocalyptic serenity towards pure apocalypse, it was suggested, that the ball of fire was replaced by a cone of debris being torn out of the face of the earth. Further, the scene was switched from day to night and the clouds were scaled down and thrown towards the horizon. The result can be seen in media all over the world, going viral as being painted by a mr. Carl Toft - godspeed to you, Carl Toft.

Yours,

Carl Christian Tofte

*A large impact crater beneath Hiawatha Glacier in northwest Greenland, Kurt H. Kjær. Nicolaj K. Larsen et al. Science Advances, 14 Nov 2018: Vol. 4, no. 11