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We are only one-third as likely to be wiped out by an asteroid as was
thought. Astronomers now say the chances of global catastrophe are 1 in 5000
over the next century rather than the previous estimate of 1 in 1500. Zeljko
Ivezic of Princeton University and his team looked at data from the Sloan
Digital Survey and found there are 700,000 asteroids bigger than a kilometre
across capable of bringing about Armageddon, fewer than previously supposed.
Compared to earlier impact risk assessments their observations also include many
more asteroids—particularly small, faint ones.