The remote Russian city of Chelyabinsk was rocked by massive meteor (see Editor's note 1) explosion on 15 February 2013 when a 10-tonne meteorite streaked over the city. Scientists from the National Aeronautics and Space Administration (NASA) estimated the force of the blast that occurred upon entering the Earth's atmosphere was about 30 Hiroshima bombs. Fortunately, there was no major damage as it occurred high in the atmosphere.
Residents of Chelyabinsk said they witnessed an extremely bright burning object in the sky. Video footage of the meteor explosion showed a fireball streaking across the sky followed by a very loud sonic boom shortly after. NASA confirmed that the object was actually brighter than the sun.
As the asteroid comes in contact with the atmosphere and it converts all the energy and creates a shockwave. Some people reported that the air in Chelyabinsk smelled like gunpowder after the explosion. The blast damaged about 4,000 buildings with pieces of shattered broken glass littered throughout the city. More than 1,200 people suffered minor injuries due to the broken glass while a few was sent to hospital for further examination. Officials have pledged to replace all the broken windows within one week. As the people of Chelyabinsk try to return to their normal lives, works have started to replace broken windows with new ones throughout the city with drilling works starting early in the morning.
Local authorities have deployed about 24,000 troops to help in the relief effort. They have also identified three potential impact sites where the meteorite could have landed. Two sites are located near Lake Cherbakul while the third is located farther northwest near the town of Zlatoust. One fragment of the meteorite was believed to have landed in the frozen lake as local fishermen found a large crater which might possibly be the result of the impact. The crater has a diameter of 6 meters. A team of six Russian divers searched the lake for fragments of the meteor however; they were not able to find anything.
Three days later on 18 February, scientists claimed they have found fragments of the meteor near Lake Cherbakul. A team of Russian scientists conducted tests on rocks that seemed unusual and confirmed that it has similar composition with a meteor. The fragments were made up of metallic iron, chrysolite and sulfite.
After confirmed news of meteor fragments found near the lake, it sparked a worldwide interest for these fragments. Russian space debris hunters are selling so-called ‘genuine’ pieces of the space rock as much as US$10,000 per piece on their websites. Local authorities have responded by cordoning off the area around the lake and prevent any media or space debris hunters near the lake. This is to ensure smoothness of the investigation by Russian authorities and scientists. Thus, deter space debris hunters from having the opportunity to sell the fragments to buyers in the black market for quick and easy money.
Editor's note 1: The terms asteroid, meteor and meteorite often get misused. Here are the correct definitions of those terms.
An asteroid is a rocky object in space that's smaller than a planet and is loosely known as space debris or leftover fragments from the formation of the solar system. There are millions of asteroids orbiting the sun. Some can be as large as hundreds of kilometres wide such as asteroid Ceres which is 940 wide. Asteroids have no atmosphere but many are large enough to exert a gravitational pull.
A meteor is an asteroid or other object that burns and vaporises upon entry into the Earth's atmosphere, like the one that was seen over Russia. Meteors are commonly known as shooting stars.
If a meteor survives the plunge through the atmosphere and lands on the surface, it is known as a meteorite. Meteorites are usually categorised as iron or stony. As the name implies, iron meteorites (see top picture below) are composed of about 90% iron while stony meteorites (see bottom picture below) are made up of oxygen, iron, silicon, magnesium and other elements.
Editor's note 2: An asteroid half the size of a football field also buzzed past Earth on 15 February, the same day as a meteor hit Russia. At its closest approach at 2:24 p.m. EST (1924 GMT), the 45-metre asteroid 2012 DA14 cruised within 27,000 kilometres of Earth. The encounter marked the closest fly-by by such a big asteroid that's ever been known about in advance.
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