This is true. Ok, that’s enough to get people doubting for a start, but scientists, astronomers and NASA state quite unequivocally that next month (Feb 2013 for those still suffering mental disorientation from the last time the world ended) a very small asteroid referred to, with rather a lack of dramatic flourish, as 2012 DA14, will go whizzing past us on 15 February.
They are sure it will miss but it will be rather too close for comfort. At only 45m across and weighing in at 130,000 tonnes, it will still be so close that it will pass between us down here and our communication satellites up there - at a distance of just 14 000 miles above our homes, if you want to put it another way. This is closer than any other asteroid of its size in recorded history. This is so close it will be visible with binoculars, if you know where to look and are in the right place.
If it were to hit earth, it would do so with the impact of an atomic bomb.
The last significant asteroid strike was in 1908, in the middle of Siberia at a place called Tunguska. That asteroid, estimated to be about twice the size of 2012 DA14, exploded between 3 and 6 miles above the earth flattening 830 square miles of forest and about 80 million trees. It killed several thousand reindeer, but no people thanks only to the remoteness of the region. Still, it serves as a chilling warning and a remarkably lucky escape.
What would happen though, if an asteroid the size of 2012 DA14 didn’t explode in the atmosphere but struck the earth directly? What kind of impact would that mean? The Barringer Crater in Arizona was made by a comparable asteroid of approximately 50 m diameter, and gives a good, and very chilling, example of what we could be facing. I happened to visit the impact site a couple of years ago and its a mighty impressive dent in the suface of the earth. However, in the context of 2012 DA14, its not a pleasant thought, given the size of the impact crater, to contemplate the consequences if something like that were to hit a modern city.
The last major asteroid impact, which is known as a meteorite if it gets to hit the earth, was probably about 3500 years ago. It landed in the Indian Ocean which is probably why there are so many legends of a great flood (Noah, Gilgamesh etc.) broadly contemporaneous with this event. It’s estimated that these rather large (1 mile across or more), terrifying and very real space visitors, infinitely more dangerous than UFOs and lesser-spotted aliens, arrive every 3000 years or so. Although this is of course a very crude measure, it does mean we are rather overdue another visit.
In cosmic terms 2012 DA14 is not just a near miss, it’s like a bullet taking a skin-thin wrist watch off your arm but leaving you unharmed. For all intents and purposes, you could just about reach out and scribble your name on it as it goes past. They don’t get much closer….and sooner or later, one won’t miss.
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