What Happens If We Nuke the Deepest Ocean Point?#

Ever wonder what would really go down if we set off humanity’s biggest nuclear weapon way, way deep in the ocean? You might think, “For sure, we’d get tsunamis hundreds of meters high wiping out coastal cities, earthquakes leveling whole countries, or even new volcanoes causing a nuclear winter.” Maybe you even picture Earth getting ripped apart or thrown out of its orbit? Well, hold up – it’s almost the opposite of that, actually.

The Location: The Mariana Trench#

Right now, the absolute deepest spot on Earth that we know of is inside the Mariana Trench. Think of it like a super deep valley tucked right where two big tectonic plates meet. It kind of looks like a mountain, but flipped upside down.

• It plunges down about 11 kilometers (that’s almost three times deeper than where the sad wreck of the Titanic rests).
• It’s one of the last places left on our planet that humans haven’t fully explored yet.
• It’s pitch black down there, and the pressure is insane – like being under a thousand atmospheres.
• Thanks to humans mostly staying away, it’s a pretty untouched, pristine environment.
• So, yeah, maybe a… great place for our little nuclear test, hypothetically speaking, of course.

The Weapon: The Tsar Bomba#

For this hypothetical test, we’d use the most powerful nuclear bomb humans have ever actually detonated. That’s the RDS-220 hydrogen bomb, famously nicknamed the Tsar Bomba.

• Its explosion was so incredibly huge back when it was tested.
• Its shockwave traveled all the way around the Earth not once, not twice, but three times.
• Its mushroom cloud shot up a whopping 56 kilometers into the sky.
• The shockwave was powerful enough to destroy everything within a thousand square kilometers.
• The fireball was hot enough to literally burn the leftover rubble.
• Bombs this size release such a massive amount of energy all at once.
• They could easily boil away an entire lake.
• And if we set one off in the Mariana Trench, well, something like that does happen initially.

Pulling the Trigger: The Underwater Detonation#

Let’s imagine we set it off.

• In the first tiny fraction of a second (the first few microseconds), the nuclear fuel does its chain reaction thing and explodes with the power of 50 megatons of TNT.
• A super bright flash of light lights up the total darkness of the trench for the very first time ever.
• The crazy heat from the blast creates a cavity – basically, a flaming bubble made of water vapor, radioactive stuff, and bits of any really, really unlucky fish nearby.
• This bubble grows super fast as it vaporizes the water right around it.
• The pressure inside this bubble is immense, pushing outwards like there’s nothing in its way.
• It sends off a shockwave that would be picked up by seismic stations and felt by whales all around the globe.

The Aftermath: Surface Effects and Fallout#

And as our mighty, destructive blast rises towards the surface… it pretty much does nothing significant on a global scale.

• You might see just a small wave on the ocean surface.
• And a bubbling plume of radioactive, warm water spreading out in the Pacific.
• No giant tsunami is going to wash away Japan or California from this.
• Though, any boats or whales right in that immediate area might have a really, really bad time.

Regarding the radioactive stuff:

• The radioactive fallout will get diluted into the huge Pacific Ocean over a few days.
• A fair amount of the radioactive water and salt does get kicked up into the atmosphere.
• It collects up there and then eventually rains back down again.
• Even if the wind happens to blow this fallout straight towards, say, the Philippines, the worst of it probably still falls over the vast, empty ocean.

What About Earthquakes and Orbit?#

Okay, but surely the real danger is the explosion setting off massive earthquakes or volcanoes, right? Even if you detonated the bomb right in the trench, exactly where the tectonic plates touch?

• Probably not.
• The explosion would vaporize a piece of the seafloor and turn a bunch of sand into glass right there.
• But most of the energy from the blast goes into the water, not into making big seismic waves that shake the ground.
• Earthquakes are already pretty common along these tectonic plate boundaries naturally.
• And honestly, earthquakes with as much seismic energy as our bomb released happen a few times every year on their own, and they don’t trigger the end of the world.

And what about changing Earth’s orbit?

• Since the test doesn’t take away any mass or add any to Earth, our orbit around the sun is completely unaffected.
• Think about it: there have been well over a thousand nuclear tests over the last 70 years, and none of those changed our orbit. So why would this one be any different?

Here’s the plain truth: The strongest forces humanity can possibly unleash are absolutely tiny, almost laughable, when compared to the massive forces of nature and the sheer size of our planet. The Earth is just too big. It simply doesn’t care about our little boom.

The Conclusion#

So, what really happens to us if we detonate a powerful nuclear weapon really, really deep in the ocean? Pretty much nothing on a global scale.

A Note on Our Videos#

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