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If a comet fragment fell into the high-pressure air of earth’s thermosphere, an explosion, known as an airburst, would release a devastating high-energy shockwave over a large area resulting in burned agricultural fields, buildings, and forests as evidenced by the Tunguska event of 1908 8. In some cases, comets such as SL9 break apart and impact planets 7. At this time, human communities and the resources they needed for survival were at a heightened risk of being destroyed by a comet airburst event.Ĭomets are dirty fractured snowballs composed of cosmic dust, frozen gases, and meteoroids 6.

Between 1,8 years ago (220 and 589 CE), Chinese astronomers documented 69 near-Earth comets (< 1.3 au and a period of revolution < 200 years), including Haley’s, which came within 0.09 au of earth in 374 CE (1646 B.P.) 5. and ~ 3000 B.P.), and one in Jordan (~ 3,700 B.P.), suggests that these natural catastrophes are far more common than previously suspected 3, 4.

The recent discovery of two Holocene cosmic impact events in Argentina (~ 6000 B.P. Both of these events are associated with global mass extinctions and they occurred before humans culturally evolved into complex, sedentary, agricultural-based societies.

Direct positive evidence of catastrophic cosmic airburst and impact events have been found in the Western Hemisphere at the Cretaceous and Tertiary (KT) boundary ~ 65 million years ago and at the Younger Dryas (YD) boundary ~ 12,800 years ago 1, 2.

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