ASTEROIDS hitting the Earth caused 26 nuclear-scale blasts between 2000 and 2013, a report reveals.
Some were more powerful - in one case, dozens of times stronger - than the 15-kiloton atom bomb that destroyed Hiroshima in 1945.
The impacts were recorded by the Nuclear Test Ban Treaty Organisation which has a global network of sensors to listen for nuc-lear weapon detonations.
Most occurred too high in the atmosphere to cause any serious damage on the ground. But the evidence is a reminder of how vulnerable the Earth is to the threat from space, say scientists.
None of the asteroids were detected or tracked in advance by any space or Earth-based observatory.
Former astronaut Ed Lu, who spoke about the new data at the Museum of Flight in Seattle, US, said: "While most large asteroids with the potential to destroy an entire country or continent have been detected, less than 10,000 of the more than a million dangerous asteroids with the potential to destroy an entire major metropolitan area have been found by all existing space or terrestrially-operated observatories."
Dr Lu is chief executive of the B612 Foundation, which is dedicated to finding ways of protecting the Earth from dangerous asteroids.
In 2013, a 600 kiloton meteor explosion above the Russian town of Chelyabinsk caused extensive damage to property.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules hereComments are closed on this article