Friday, November 18, 2011

Once Upon a Falling Star - Published in the Mail & Guardian (November 18, 2011)

Once Upon a Falling Star - by Nick van der Leek


A very long time ago, something earth shattering happened on a landmass we know today as the Free State.

In fact, as far as we know, it is probably the most earth shattering event subsequent to the creation of the moon that has ever taken place on Earth. If the big sky plains of the Free State seems a strange place for an earth shaking event, the event itself could not be more bizarre, spectacular and indeed, bone rattling.

For background, remember that the earth is estimated to be 4 500 million years old, and the moon 4 450 million year old (created when a planet destroying 3000km wide rogue rock collided -- a glancing blow to the present north pole -- into our molten planet). Then, 2 023 million years ago, some people believe that a UFO 10 kilometres wide, or about the size of Table Mountain and traveling at 200 000km/h through space, made a bullseye for the present-day northwestern Free State.

The collision caused a magnitude 14 earthquake on the Richter scale, 100 000 times more powerful than the 1979 Tangshan earthquake (the largest 20th century earthquake by deathtoll). A portion of the earth's atmosphere incinerated, molten rock and acid rain fell over a large area, and tsunamis several hundred metres high swept the Earth's oceans.

The entire planet cooled down over the next few years as a huge dust cloud enveloped the planet. An event that changed the fate of all life on earth lasted just 4 minutes. It is hard to believe the whispering veld between Welkom in the south, and Johannesburg in the north, is the setting of a cataclysm that changed the fortunes of all living creatures today.

But while the furious impact near Vredefort is the largest and oldest that we know of, impact craters on the moon are up to six times larger. And while a majority of scientists agree that either a comet or a large asteroid pummeled the gentle Free State plains, a vital piece of evidence remains at large.

Some skeptics have noted that an extra-terrestrial body would have deposited one of the heaviest elements at the site, a substance known as iridium. (Because of its exceptional hardness, iridium is used, for example in the iridium alloy nib of the Parker 51 fountain pen).

Read the remainder of this article.

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