In the wake of Halloween last week a very, very scary scientific paper was published. “Widespread glasses generated by cometary fireballs during the late Pleistocene in the Atacama Desert, Chile,” Shultz et al.”(October, 2021) creates a rebuttable presumption that horrific cosmic airbursts — without leaving craters — have indeed occurred in human history, a decade long contention here at the Tusk.
The chilling part is that evidence for this type of atmospheric hell storm can be difficult to detect, and therefore we have no idea how often they occur. If the explosions didn’t happen in the last 300 years or so, like Tunguska, it is unlikely they would be “recorded,” except as wild sounding myth, oral traditions of illiterate villagers, and spiritual recollections.
And again, like Tunguska, within a few generations there would not be anything more than microscopic evidence at the location of the blast. But fortunately, the special conditions of the Atacama Desert, and other deserts, reveal evidence of fire from the sky more easily than in say…Ohio.
Shultz et al. provides yet more physical evidence that Planet Earth and humans have encountered showers of fragile comet debris that impact the atmosphere — but do not ding the earth itself. Kinda like bridge jumpers who don’t deform the river bottom, but do find a very hard, energetic stop on the way down.
Due to the extreme change in density from outer space to air, a whole class of incoming debris — the vast majority — never dig a hole. They just blow up in the atmosphere and create ferocious blasts exceeding the most awful nukes ever devised. And, like nuclear bombs, depending on the altitude of the blast (and in the case of space debris, the angle of entry) they don’t leave behind craters.
To make matters worse, they also come in swarms:
The distribution and general similarity of glasses with the same entrained meteoritic clasts at widely separated locations require either successive low-altitude breakup of a single body with a low-angle trajectory or a series of tidally disrupted bodies entering the atmosphere at relatively high angles (>30° from the horizontal), analogous to the Shoemaker-Levy 9 collision by a fragmented cometary body on Jupiter. ~Shultz, 2021
The paper puts the date of the Chilean hellstorm at 12,500, which is notable to the Tusk because it is very close to the YD impact and climate crash date of ~12,800. A 2.4% discrepancy is good enough for government work, you might say. But it also provokes my suspicion that Pete Shultz could be dead right on the date, and we are seeing evidence supporting the work of Clube and Napier.
To wit: The Taurid meteor stream presents repeated threats, which wax and wane through the millennia since a giant comet entered our solar and began disintegrating ~20,000 years ago.
As Bill Napier put it to me, its like highway traffic. Depending on the time of the day — or portion of millenia/or given span of time — you can have very busy periods where crossing the highway (blindfolded as we are) is deadly from a thousand points, and others where you could more likely cross safely. It’s a chaotic state with some elements of predictability. Current impact frequency analysis by NASA and others consider the highway to be equally busy at all times of the day, year round, for millennia.
So the Younger Dryas encounter can be thought of as a very bad stretch of traffic — obviously with some trucks — which may have been preceded and followed by pulses of lesser events within hundreds of years.
I’m left to wonder if Shultz et al. somehow managed to have this profound paper published in the week of “peak traffic” for the Taurid Stream, in late October/early November. That would be creepily fitting, since Halloween appears to be a cultural artifact of the repeated fall traumas.
Our results have three important implications. First, the Pica glasses illustrate the difficulty in recognizing such [airburst] events due to the poor geologic expression at the time of formation, the soil conditions necessary for glass generation, and the low preservation potential. Consequently, these glasses provide a unique, well-preserved recent record that can be used to constrain details about the formation process and the frequency of similar airbursts. Second, the dates for the Pica glasses coincide with the disappearance of Qua-ternary megafauna in South America, an extinction that was more severe than that on any other continent (Barnosky and Lindsey, 2010). While a direct causal link is not claimed, the timing is intriguing. Third, the entrained mineral assemblages are most consistent with a cometary body. Recent studies suggest that more than 16% of the objects >3 km in diameter hitting Earth may be cometary (Quintana and Schultz, 2019), which is higher than some previous estimates (e.g., Weiss-man, 2007). Such an airburst would affect a much broader area than a cratering event (for an equivalent-mass object), as demonstrated by the numerous airburst scours on Venus (e.g., Schultz, 1992) and entry models for Earth (Boslough, 2014)