While there is no chance that asteroid 2012 DA14 will hit Earth this Friday (Feb. 15), the asteroid's flyby is history-making for several other reasons.
For one thing, scientists will have the unprecedented chance to get an up close and personal view of the near-Earth asteroid, which is half the size of a football, as it passes by the planet at a distance of just 17,200 miles (27,000 kilometers).
What do we know about asteroid 2012 DA14?
Asteroid 2012 DA14 is a little guy, compared to some asteroids, although its size has not been pinned down precisely. It is thought to be about 45 meters across (nearly 150 feet across), with an estimated mass of about 130,000 metric tons.
If a space object 150 feet wide were to strike our planet, it wouldn’t be Earth-destroying. But it has been estimated that it would produce the equivalent of 2.4 megatons of TNT. How does that compare with other known impact events on Earth? In 1908, in a remote part of Russia, an explosion killed reindeer and flattened trees. But no crater was ever found. Scientists now believe a small comet struck Earth. That event has been estimated at 3 to 20 megatons. So 2012 DA14 is in the same approximate realm as the Tunguska comet (which, actually, might have been an asteroid instead). It would not destroy Earth, but it could flatten a city.
Of course, about 70% of our world is covered by oceans. That means the most likely landing spot of any incoming asteroid is in the water – not on a city or other populated area.
Astronomers at the Observatorio Astronómico de La Sagra in Spain discovered 2012 DA14 in early 2012. We know 2012 DA14′s orbit is similar to that of Earth. That is one reason the asteroid eluded astronomers until recently. You can be sure that many astronomers are carefully tracking 2012 DA14 now.
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