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[How to Stop a Killer Asteroid: From Nukes to Cosmic Penetrators]-[Can Humanity Stop A Planet-Killing Asteroid?]

Kurzgesagt – In a Nutshell · B1 ·

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📋 Summary

The Looming Threat: Why We Are Unprepared for Killer Asteroids

Humanity faces a silent, existential threat: asteroids that can strike with the destructive power of thousands of Hiroshima bombs. Recent history shows that these objects—such as asteroid OK and asteroid MK—are often detected only days before they pass dangerously close to Earth. Despite the immense danger, we currently lack a robust defense strategy. Traditional deflection methods, such as painting surfaces or using thrusters, are akin to "trying to deflect a cargo ship by throwing a bag of potatoes at it." These techniques require years or decades of lead time, which we rarely have.

The Failure of Conventional Solutions

The intuitive approach of using nuclear weapons faces significant physical hurdles in space. A head-on collision is impossible because the asteroid would destroy the warhead before detonation. Detonating a nuke near the surface is equally ineffective; without air to carry a shockwave, most of the energy is lost in the vacuum of space, leaving the asteroid largely intact. Even the "Hollywood" approach of landing a crew to drill and bury a bomb is practically impossible due to the nightmares of landing in microgravity and the extreme time constraints involved in intercepting a high-velocity threat.

The "Lumberjack" Strategy: Cosmic Penetrators

Instead of trying to push these bodies, we must think like a lumberjack and use a tool designed to break them apart. Scientists have proposed using "penetrators": slim, ultra-dense tungsten rods that act as cosmic bullets. By placing these stationary in the path of an oncoming asteroid, the relative impact speed—70,000 kilometers an hour—turns the penetrator into a weapon of immense force. The kinetic energy released, equivalent to 120 metric tons of TNT, vaporizes the tungsten and carves a deep wound into the asteroid, pulverizing it into a diffuse cloud of debris. When this cloud reaches Earth, the fragments are small enough to burn up harmlessly in the atmosphere, turning an apocalypse into a "cosmic fireworks" show.

The Ultimate Challenge: Defeating a Planet Killer

The danger escalates significantly when facing a "planet killer," such as a comet from the outer solar system. Traveling at 140,000 kilometers per hour, these icy mountains are too massive to be destroyed by a single penetrator; breaking them into large pieces would still cause catastrophic damage. To survive a planet killer, we must destroy it far beyond the orbit of Mars.

This requires a sophisticated, high-stakes operation:

  1. Sequential Penetration: Deploying multiple penetrators in a line to drill deep into the comet's core.
  2. The Nuclear Coup de Grâce: The final penetrator carries a massive nuclear payload—300 megatons—which detonates deep within the tunnel created by the previous impacts.

By trapping the nuclear energy inside the comet’s structure, the explosion causes the frozen world to shatter from within. While this plan requires unprecedented precision and the immediate availability of super-heavy rockets, it remains a theoretically viable defense using technology that exists today. By shifting our focus from passive deflection to active destruction, humanity can move from being helpless victims of cosmic chance to active protectors of our planet.

🎯Key Sentences

1
This isn't science fiction.
2
Stunningly enough, humanity doesn't really have a plan for this.
3
They're the equivalent of trying to deflect a cargo ship by throwing a bag of potatoes at it.
4
the obvious choice is, of course, a nuke.
5
So let's go.
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📝Key Phrases

1
at the last moment
2
devise a plan
3
in advance
4
at the expense of
5
break things apart
Expand All

📖 Transcript

Our first ever PC game, Starbirds, is out now in Early Access.
Find out more at the end of this video.
Imagine, a stadium-sized asteroid is going to hit Earth in two weeks.
Even at this moderate size, a fireball brighter than the Sun tears through the atmosphere at 60 times the speed of sound and the destructive power of 4000 Hiroshima bombs, flattens cities, killing millions.
This isn't science fiction.
Many killer asteroids were only spotted at the last moment.

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