Russian Meteor

   NASA cannot monitor most potentially devastating asteroids

Although the 150ft (45m) rock will zoom harmlessly by our planet on its record near approach in February 2013, it is just one of up to a million "near-Earth objects" which astronomers believe could one day pose a serious threat.

A program set up by NASA to monitor so-called "NEOs" a decade and a half ago has so far tracked fewer than 10,000, meaning the vast majority are still hidden.

Most of the larger specimens, which could have the potential to wipe out entire continents, have been found but even small asteroids like 2012 DA14 could be powerful enough to destroy an entire city if they plunged down to Earth.

Now experts are calling for greater monitoring of small NEOs measuring less than a kilometre across, and for a contingency plan in the event of a likely impact.

UK Space Agency engineers travelled to the United Nations this week to seek a deal with colleagues from around the world and hope to come to an agreement before Friday. The first goal is to secure funding for asteroid monitoring from countries other than America, which pays for the majority of the current program.

   2011 EO40

The meteor fireball, also known as a superbolide, was seen over Chelyabinsk in the south of the country near the border of Kazakhstan and around 900 miles east of Moscow.

It exploded over Russia's Ural Mountains and is the biggest space rock to have hit earth in more than a century.
The 10,000 tonne rock, measuring around 55 feet in diameter, created a huge hole in a frozen lake when it crashed into the ground.

Over 1,000 people were injured by the exploding rock and scientists managed to recover more than 50 tiny fragments of the meteor, allowing them to study its contents and origin.

Nasa scientists at the time said the shockwave caused by the crash was greater than 30 Hiroshima nuclear bombs and was so powerful it travelled twice around the world.

The Russian meteor hit the Earth just hours before an asteroid called 2012 DA14 was spotted nearby but the two incidents were not found to be related.

Professor Carlos de la Fuente Marcos and his brother Raul from the University of Madrid identified 20 possible sources from a cluster of asteroids dubbed Chelyabinsk asteroid family.

They told The Telegraph: 'The most probable parent body for the Chelyabinsk superbolide is 2011 EO40. Under such conditions, the cluster cannot be older than about 20,000–40,000 years.'

However, the only way to confirm this theory, claims Marcos, would be to go into space and take samples of the 2011 EO40 asteroid.

German scientists are also set to publish finding later this year that claim the meteor was made of a stony material called chondrite breccias.Most asteroids are made up of boulders, dust and ice.

Professor Carlos de la Fuente Marcos added that another similar incident is 'unlikely' but smaller fragments might crash to Earth as the asteroid continues its orbit.

The meteor caused widespread property damage in Chelyabinsk city, with health officials saying that 46 of the injured remain hospitalised.

The debris narrowly missed a direct and devastating hit on the industrial city which has a population of 1.13 million but spread panic through its streets as the sky above lit up with a blinding flash.

Paul Chodas of NASA's Near-Earth Object Program Office said at the time: 'We would expect an event of this magnitude to occur once every 100 years.'

He told the Wall Street Journal: 'When you have a fireball of this size we would expect a large number of meteorites to reach the surface and in this case there were probably some large ones.'

Viktor Grokhovsky, who led the expedition from Urals Federal University, said that 53 fragments of the meteor had been plucked from the ice-covered Chebarkul Lake.

The local governor estimated the damage at 1 billion rubles (£21.5million) and said he hopes the federal government will provide at least half that amount.

Lidiya Rykhlova, head of the astronomy department at the Moscow-based Institute for Space Research, said experts have drafted a program that envisages building powerful telescopes, including space-based ones, to warn against potentially dangerous asteroids, comets and other threats.

As it raced through the sky, the 50-foot wide chunk of space rock compressed the air ahead of it, creating the enormous temperatures that meant it exploded in a fireball somewhere between 18 and 32 miles above the ground at around 9.20am local time on 19 February.

Although some debris fell to earth, ‘whipping up a pillar of ice, water and steam’ and creating a 20-foot-wide crater, the damage in nearby towns was actually caused by shockwaves created by the meteor breaking the sound barrier and then exploding.

The city of Chelyabinsk, 900 miles east of Moscow and close to the Kazakhstan border, took the brunt of the impact

Collectors from around the world will be keen to get hold of a piece of the meteor. Film director Steven Spielberg is a noted collector. In October a 9in piece of the Seymchan meteorite found in Siberia in 1960 sold in New York for $43,750 (£28,200).

Astronomers have also revealed that the meteor could have hit UK cities if it had hit at a slightly different time of day.

   Russian Meteor Shock Rippled Around Earth, Twice

Although interesting, other astronomers suspect that the projected orbit of the Chelyabinsk asteroid and its similarity to other known near-Earth asteroids is more of a coincidence rather than the smoking gun.

“I think that the resemblance of orbits is coincidental,” said David Nesvorny, of the Southwest Research Institute in Boulder, Colorado. “It is not obvious to me why (the Chelyabinsk meteor) cannot be a fragment that was produced by a collision in the main asteroid belt, and evolved to its impact orbit by a few planetary encounters.”

The de la Fuente Marcos brothers admit that further observations of asteroids in the candidate cluster are needed to refine their orbits, but the ideal method to confirm the nature of the Chelyabinsk meteor would be to compare samples of fragments of the Russian “superbolide” and compare it with samples returned from 2011 EO40. A cheaper, though less accurate, method would be to gather high-resolution spectra of reflected light off those objects in the hope of understanding their composition. Only then will the true nature of the destructive Chelyabinsk meteor be identified.

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