A Nuclear Explosion Could Protect Earth From An Asteroid

Nuclear Explosions as a Defense Against Asteroids

Precisely detonating a nuclear bomb above an approaching asteroid could be our best chance of avoiding a catastrophic impact.Precisely detonating a nuclear bomb above an approaching asteroid could be our best chance of avoiding a catastrophic impact.

A laboratory experiment conducted by an international team of researchers showed that the X-rays generated by a suitably sized nuclear explosion could shift asteroids about 3 to 5 kilometers in diameter off their trajectory.

The Importance of a Disaster Prevention Plan

While scientists do not presently need such an anti-catastrophe device, they recognize that the threat of unexpectedly encountering a near-Earth asteroid is serious enough to warrant the creation of a robust disaster prevention plan.

Recently, NASA showed that a heavy space probe could deflect a small pile of rocks from Earth’s path with a strong collision. The smaller component of the Dimorphos and Didymos binary system, under 800 meters in diameter and made of loose gravel, was displaced from its orbit, boosting scientists’ confidence in using directed collisions to shift similarly sized objects away from Earth.

While these results are promising, researchers clearly need more data before they can attempt to deflect any asteroid by merely hurling probes at them. A larger, more solid asteroid could pose a completely different challenge.

Alternative Methods for Moving Asteroids

Fortunately, there are other ways to move an asteroid. Attaching it to a powerful fusion engine or using focused lasers to evaporate part of its surface and create a rocket-like effect are some options.

However, one feasible method involves heating a small area of the asteroid’s surface with intense radiation, which could vaporize minerals and generate gases that push the asteroid off its course.

Researchers can test the basic principles of evaporating rock with electromagnetic radiation on Earth, making adjustments for different materials and mineral structures.

A team led by physicist Nathan Moore, from Sandia National Laboratories in the U.S., used a high-frequency electromagnetic wave generator called the Z Pulsed Power Facility to release 1.5 megajoules of X-rays into a tank of argon gas.

Simulating Asteroid Deflection in the Lab

This radiation “bubble” destroyed a thin metal foil holding a grain of fused silica (or quartz glass), suspending the sample just long enough to simulate a small asteroid drifting through space.

Moments later, the X-ray pulse hit the target, stripping micrometers from its surface and generating shock waves that provided crucial data.

These results could help predict the effects of a larger X-ray burst in the interplanetary vacuum. The momentum transfer suggests that asteroids up to 5 kilometers in diameter could theoretically be shifted using this method.

The team reported that researchers can test detailed models, such as the radiation-hydrodynamic model shown here and in other studies, against experimental data from this technique to refine predictions for asteroid intercept missions.

Testing Various Asteroid Compositions

Of course, researchers know that asteroids consist of more than just fused silica; they often contain a mix of volatile materials arranged in various ways. By using this approach, scientists can test different scenarios without needing to launch expensive missions and wait years for results.

Ideally, scientists will never need this knowledge. Although predictions indicate that some city-killer asteroids will pass dangerously close to Earth, none currently pose an immediate threat.

Still, no one likes surprises.If a real threat comes hurtling out of the darkness, we should know exactly how to blast it back into oblivion.

Read the original Article: Science Alert

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