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 hypercanesripped
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.
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