Asteroid warning: How a 20-mile wide asteroid could head for Earth – and stay UNDETECTED

A giant 20-mile asteroid could remain undetected on a collision course towards Earth, an expert has revealed. Earth Science author Corey Powell gave a “qualified” yes when asked whether a apocalyptic asteroid could surprise experts on Earth in only 20 years. He wrote on Quora: “The killer could not come from the asteroid belt.

“Astronomers have already plotted the orbit of every asteroid that size (and a lot smaller) in great detail.

“There is no object that size that could plausibly hit Earth any time in the next few thousand years — probably not in the next few million years.”

But there is only one way an such an armageddon astroid could make an unexpected rendezvous with Earth.

Mr Powell added: “If it were a giant comet or dislodged Kuiper Belt Object coming toward us on an extremely elliptical path (ie. falling almost straight toward the Sun), it would be very hard to detect.

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What would be the consequences of a 20-mile wide asteroid hitting Earth?

A 20-mile wide asteroid is approximately two to three times the diameter of the space rock that hit Earth at the end of the Cretaceous period.

Compounding the problem, the asteroid would also be moving at a high velocity, given its steep path toward the Sun.

Such an asteroid could consequently pack 100 times the energy of the impact that destroyed the dinosaurs, meaning this would be a literal extinction-level event.

Mr Powell, a former editor of revealed the unimaginable catastrophe that would follow such as asteroid strike.

He said: ”All of Earth’s surface would be set on fire.

“There would be tremendous earthquakes and tsunamis, followed by massive volcanism around the impact zone.

“The ozone layer would be destroyed. The oceans would turn acidic. The Sun would be blotted out, probably for decades.

“All surface infrastructure would be destroyed. Most complex species would surely perish in the aftermath.”

How could humanity defend itself against such an asteroid?

Mr Powell believes the approach with the highest likelihood of success would be to explode multiple nuclear warheads next to the asteroid, vaporising part of its surface and changing its orbit.

He said: “If NASA, Roscosmos, the European Space Agency and the Chinese space agency (plus private industry) started cooperating right away, I can imagine that a coordinated set of launches could take off in about 2 years, and would intercept the asteroid about 10 years after that.

“Unlike many of the cynics, I think that kind of international cooperation would happen.

“The threat is just too huge. All other concerns would become secondary; there will be no nations and governments to worry about if this thing hits.”