A Blast From the Past

How destructive could an asteroid strike be? What would it be like? Bill McGuire, an expert on natural catastrophes and professor of geohazards at University College London, describes the events that created the Chicxulub crater,buried deep beneath the Yucatan Peninsula and Gulf of Mexico and discovered only recently:

"Here a 10-kilometre [6-mile] asteroid or comet—its exact nature is uncertain—crashed into the sea and changed our world forever. Within microseconds, an unimaginable explosion released as much energy as billions of Hiroshima bombs detonated simultaneously,creating a titanic fireball hotter than the Sun that vaporized the ocean and excavated a crater 180 kilometres [112 miles] across in the crust beneath.

"Shock waves blasted upwards, tearing the atmosphere apart and expelling over a hundred trillion tonnes [metric tons] of molten rock into space,later to fall across the globe. Almost immediately an area bigger than Europe would have been flattened and scoured of virtually all life, while massive earthquakes rocked the planet. The atmosphere would have howled and screamed as hypercanes ripped the landscape apart, joining forces with huge tsunamis to batter coastlines many thousands of kilometres distant.

"Even worse was to follow. As the rock blasted into space began to rain down across the entire planet . . .the heat generated by its re-entry into the atmosphere irradiated the surface,roasting animals alive as effectively as an oven grill, and starting great conflagrations that laid waste the world's forests and grasslands and turned fully a quarter of all living material to ashes.

"Even once the atmosphere and oceans had settled down, the crust had stopped shuddering, and the bombardment of debris from space had ceased, more was to come. In the following weeks, smoke and dust in the atmosphere blotted out the Sun and brought temperatures plunging by as much as 15 degrees Celsius [27 degrees Fahrenheit].In the growing gloom and bitter cold the surviving plant life wilted and died . . .

"Life in the oceans fared little better as poisons from the global wildfires and acid rain from the huge quantities of sulphur injected into the atmosphere from rocks at the site of the impact poured into the oceans, wiping out three-quarters of all marine life" ( A Guide to the End of the World, 2002, pp. 159-161).

Especially sobering is how closely these descriptions—scorching flames,enormous conflagrations,suffocating darkness and poisoned water and atmosphere—parallel events prophesied in the book of Revelation. GN