Asteroids have long been one of the most significant existential threats to life on Earth. The catastrophic impact of a large space rock 66 million years ago is well known—it wiped out the dinosaurs and triggered one of Earth’s five major extinction events. Today, the possibility of another asteroid on a collision course with our planet looms as an ever-present danger. However, a recent study brings renewed hope, suggesting that nuclear bombs might be the key to averting such an extinction event.
A team of researchers at Sandia National Laboratories in the U.S. has explored the possibility of using nuclear explosions to alter the course of a planet-killing asteroid. According to their experiments, the intense X-ray pulse from a nuclear detonation could vaporize part of an asteroid’s surface, effectively nudging it in a different direction. This approach, rooted in Newton’s third law of motion, suggests that by vaporizing material on one side of the asteroid, the resulting gas will exert enough force to push the space rock off its deadly path.
\The Science Behind the Plan
In their experiments, the researchers used a 'surrogate asteroid material' and exposed it to intense X-ray pulses. The radiation destroyed the structural integrity of the material, causing it to vaporize. The rapid vaporization produced an expanding gas, which in turn created a push in the opposite direction. The team found that this method could deflect an asteroid up to 5 kilometres in diameter.
What makes this strategy particularly exciting is its potential effectiveness. Nathan Moore, the lead author of the study published in Nature Physics, explained that the intense X-rays generated by the nuclear blast would vaporize parts of the asteroid, creating a powerful and directional force that could shift its trajectory. In their experiments, the researchers observed that small bits of asteroid material flew off at over 320 km per hour. This proves that, theoretically, even a space rock of considerable size could be deflected far enough to avoid Earth.
The Nuclear Debate
While the nuclear option is compelling, some scientists caution that this approach carries its own risks. Blowing up an asteroid could result in thousands of debris fragments, many of which might still pose a threat to Earth. Each fragment would have to be accounted for, and smaller pieces might cause widespread damage if they enter the Earth's atmosphere.
Despite this, many experts argue that nuclear deflection may be the best available option for dealing with large, undetected asteroids that are discovered too late for other mitigation strategies, like NASA’s planned NEO Surveyor telescope, which will launch in 2027 to help detect asteroids.
Lessons from Past Missions
The idea of changing an asteroid’s trajectory is not just theoretical. In 2021, NASA launched the DART mission to intentionally deflect a small asteroid named Dimorphos. The mission was a resounding success, proving that humans can indeed alter the course of space rocks. The European Space Agency (ESA) is building on this with its upcoming HERA mission, set to launch soon, which will study the aftermath of DART and help scale the technology to deal with larger asteroids.
Conclusion
As humanity looks to the stars, the threat of asteroid collisions remains a pressing concern. However, advancements in science, such as the nuclear deflection strategy, give us hope that we can prevent another mass extinction event. While risks remain, the possibility of using nuclear bombs to save the planet from a catastrophic asteroid strike is a bold and promising solution that could one day save humanity from a planet-killing disaster.