Dangerous near-Earth asteroids ‘could be 1,000 times more powerful than Hiroshima nuke’

A LARGE asteroid striking Earth could release a thousand times more energy than a nuclear bomb, according to one scientist.

Speaking to the New York Times last week, astronomers warned of the devastating impact a rogue space rock could have on our planet.

GettyAn asteroid of the size that wiped out the dinosaurs could strike Earth again[/caption]

Most near-Earth asteroid large enough to cause global devastation have been spotted by researchers.

Programmes run by Nasa keep a round-the-clock watch on thousands of so-called near-Earth objects (NEOs) that could pose a threat.

However, NEOs measuring roughly 460 feet across number in the tens of thousands and could do significant damage.

Half remain unidentified and can create city-razing blasts “larger than any nuclear test that’s ever been conducted,” Megan Bruck Syal, a planetary defence researcher at the Lawrence Livermore National Laboratory, told NYT.

Earthlings are in for a “really bad day” even if an asteroid just 160 feet across were to strike, she added.

One a few hundred metres across devastated 800 square miles of forest near Tunguska in Siberia on June 30, 1908.

“That’s still 1,000 times more energy than the Hiroshima explosion,” Dr Bruck Syal said.

It’s thought that just one in ten of near-Earth objects in this size range have been discovered.

Thousands of so-called near-Earth objects (NEOs) are tracked by space agencies to provide an early warning if they shift onto a collision course with our planet.

Any object that comes within 4.65 million miles of us is considered “potentially hazardous” by cautious space organisations.

Earth hasn’t seen an asteroid of apocalyptic scale since the space rock that wiped out the dinosaurs 66million years ago.

However, smaller objects capable of flattening an entire city crash into Earth every so often.

Fortunately, Nasa doesn’t believe any of the NEOs it keeps an eye on are on a collision course with our planet.

That could change in the coming months or years, however, as the space agency frequently revises objects’ predicted trajectories.

“Nasa knows of no asteroid or comet currently on a collision course with Earth, so the probability of a major collision is quite small,” Nasa says.

“In fact, as best as we can tell, no large object is likely to strike the Earth any time in the next several hundred years.”

Should a city-flattening asteroid threaten our planet, there’s not a whole lot that scientists could do.

Astronomers are analysing how nuclear weapons may one day be used to divert or annihilate dangerous space rocks.

Later this year, Nasa’s Double Asteroid Redirection Test space mission will smash into an asteroid in a bid to alter its orbit around the sun.

The mission is intended as a test run for the day when we need to slam a space rock out of Earth’s way for real.

A giant mushroom cloud rises over Hiroshima after an atomic bomb razed the city on August 6, 1945Getty

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