Threat From Deadly Asteroids 'Ten Times Worse' Than Previously Thought?
The risk of large asteroids hitting Earth is ten times larger than we previously thought, according to a new study.
Three extensive studies of the asteroid which exploded above the Russian town of Chelyabinsk in February, resulting in injuries to 1,000 people, shows that it was not as extraordinary as previously thought.
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Peter Brown, a planetary scientist at the University of Western Ontario, says that while the estimated rate of similar impacts is about once in 150 years, the observed rate is orders of magnitude higher.
In his study, Brown and his team show that number of impacts over 1 kiloton of TNT could be up to ten times higher than previously thought.
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http://www.huffingtonpost.co.uk/2013/11/07/deadly-asteroids-threat_n_4230981.html