Armageddon was RIGHT! We really could nuke asteroid heading for Earth

The 1998 sci-fi classic Armageddon might not have a reputation as a scientifically accurate film. 

But scientists now say the Hollywood blockbuster got one thing right – we really could nuke an asteroid out of its deadly collision course if it were heading towards Earth.

This technique is called nuclear deflection and, unlike in the movies, the goal is not to blow the approaching asteroid into smithereens.

Instead, a precisely timed nuclear explosion could give the asteroid just enough of a nudge to sail harmlessly past Earth.

Until now, experts have raised concerns that nuclear deflection would shatter an asteroid into many pieces, which would collectively pose an even greater risk.

However, a new simulation shows that asteroid material is actually far more resilient to extreme forces than previously thought.

Researchers from the University of Oxford found that some asteroid material actually gets stronger when subjected to an intense impact.

This means we could use huge nuclear weapon to deflect an incoming asteroid, without shattering it into deadly shrapnel.

For the study, the researchers teamed up with nuclear deflection startup, the Outer Solar System Company (OuSoCo), to find out what would happen to a metal-rich asteroid if it was nuked.

Unsurprisingly, it isn’t possible to let off a nuclear weapon inside a lab, so the scientists turned to the next best thing: a massive particle accelerator.

The researchers used CERN’s 4.3 mile (7km) Super Proton Synchrotron to blast a fragment of a meteor with a stream of high-energy protons – stable positively charged particles found inside atoms.

A piece of the Campo del Cielo meteorite, a metal-rich iron-nickel body, was exposed to 27 successive short bursts from the particle accelerator to simulate the impact of a nuclear blast.

Bizarrely, the researchers watched as the asteroid material softened, flexed, and then unexpectedly strengthened without breaking.

Co-lead author Melanie Bochmann, co-founder of OuSoCo, says: ‘The material became stronger, exhibiting an increase in yield strength, and displayed a self-stabilising damping behaviour.’

Overall, while being hit with the force of a nuclear blast, the asteroid’s strength actually increased by a factor of 2.5.

This new evidence is a strong suggestion that nuclear deflection could be a viable option for planetary defence.

Thousands of pieces of space rock hit the Earth every single year, but the vast majority of these are so small that they simply burn up in the Earth’s atmosphere.

However, asteroids large enough to cause serious damage do arrive with surprising frequency.

Most recently, the Chelyabinsk explosion injured thousands of people in 2013 when an 18-metre (59ft) asteroid broke up in the atmosphere.

To protect Earth from an even bigger strike, NASA and the European Space Agency (ESA) are currently researching a technique called a ‘kinetic impactor’.

This very simply involves slamming a spacecraft into the side of an asteroid as fast as physically possible so that the transferred kinetic energy moves it off course.

NASA’s 2022 DART mission, which smashed a spaceship into the asteroid Dimorphos, proved that this could move an asteroid enough to save Earth.

However, kinetic impactors only work if astronomers have spotted the asteroid years before its arrival, to give time for the small changes in trajectory to build up.

Ms Bochmann told the Daily Mail: ‘Space agencies already recognise the necessity of nuclear deflection.

‘For large objects or scenarios with short warning times, it is widely regarded by space agencies and experts as the only viable deflection option.’

The fact that metal-rich asteroid material is so resilient to high-energy impacts is a good sign for the prospects of nuclear deflection, since it suggests that nuking a space rock won’t cause fragmentation.

‘The paper shows that significantly more energy can be delivered by a nuclear explosion without causing catastrophic fragmentation of the object than previously assumed,’ says Ms Bochmann.

However, before NASA starts launching nuclear warheads into space, a lot more research will be needed.

This paper only looks at one very specific type of asteroid – metal-rich iron-nickel – whereas world-ending threats come in all shapes and sizes.

The researchers now plan to repeat the study with samples from a more complex class of asteroid.

These could include meteorites called pallasites, which are similar to the samples already studied but with centimetre-sized, magnesium-rich crystals embedded inside.