A couple weeks ago I wrote about the
asteroid that was going to fly by the Earth. Which it did, since
we're all still here to read this. But at almost the same time,
February 15th, a meteor did come down on Chelyabinsk area
of Russia (in the Ural Mountains). And it was big, though not
particularly huge, at about 55 feet and weighing in at about 10,000
tons. It was certainly big enough to cause a lot of injuries and
damage.
Rather than strike the ground the
meteor exploded about 10 miles up, which spread the damage over a
wider area, but did keep the overall severity of the damage down. The
amount of energy that was released, was somewhere close to 500
kilotons, which is about 30 times the size of the Atomic Bomb that
was used on Hiroshima.
Somewhere around 1,500 people were
injured by the meteor, however almost all the injuries were pretty
minor. Most of them caused by flying pieces of glass. But some
injuries were more severe with a small number of people hospitalized
briefly.
The meteor took a considerable amount
of time to fly across the sky, giving many people a chance to capture
video of the event. If you are interested some of these are available
of YouTube, one link is http://www.youtube.com/watch?v=90Omh7_I8vI.
With the brightness of the explosion the fireball was seen for a
large distance. (Exploding meteors are sometimes called bolides.
I was exposed to one many years ago in Texas. I say exposed rather
than saw, since I was facing the other direction and saw the light,
and my shadow on the ground in front of me. My friends that were
facing me actually got to see the explosion.)
Given how well observed this
particular meteor was, it is no wonder that it wasn't long before
people had tracked down fragments of the meteor. Some fragments (at
least purported fragments) are available to buy on Ebay (prices vary
by size). Other fragments have been sent to various scientific
centers to undergo investigation.
These fragments have shown that the
meteor was of a type known as a chondrite. Chondrites are
rocky meteors, made up of dust and small grains that came out of the
cloud of material that formed the early solar system billions of
years ago. This means they are basically unchanged from the types of
things that first made up the planets and larger asteroids. Most
meteors are chondrites. These small pieces of rock contain examples
of minerals such as olivine
and pyroxene,
which aren't formed on planets.
So a small piece of rock (relatively
small at least) hits the Earth. Russian entrepreneurs are making
money on Ebay selling fragments, scientists get some new samples of
the early solar system to study. Almost all the injuries were pretty
minor. The economic impact is only about $30 million. Life is good.
But let's keep science looking up, even a little warning might have
helped to prevent some of those injuries. Such meteor strikes are
rare events, so we probably have time before the next one, but let's
not gamble with the whole nest egg.
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