# Is it possible to create a bomb powerful enough to wipe out all life on the planet?

Would it be possible to create a bomb powerful enough to turn the entire planet into an inhospitable wasteland devoid of life, with technology available to us right now?

Would this bomb be able to evaporate away the oceans and destroy the ozone layer, effectively killing all life on earth?

Just to make it clear, the evil mastermind making this bomb is rich enough that money is not an issue and he has enough scientists and workers to manufacture this bomb, so would it be possible?

• No, it isn't. The most powerful bomb ever made, the Tzar Bomba, was equivalent to 50 megatons of TNT (210 PJ). That's comparable to the energy released by a puny earthquake measuring 4.5 on the Richter scale; about 10,000 such earthquakes happen annually and nobody cares. The Chicxulub impactor which may have contributed to the extinction of non-avian dinosuars released an energy equivalent to a magnitude 11 earthquake, and life carried on. – AlexP Jan 10 '18 at 23:58
• I'm confused why this is tagged as "magic" when in the question is "technology available to us right now"? – Austin A Jan 11 '18 at 0:17
• From what I understand, there isn't really a hard cap on the size of a fission weapon, only the delivery system. If you were to create a massive installation to house an enormous stationary bomb, it could theoretically be possible. I don't have hard numbers for you, just relaying information I've read in the past. – DMQ Jan 11 '18 at 2:51
• @DMQ I think you mean there's no hard cap on the yield of fusion weapons. Wild rumor claimed that Teller had a design for a 10,000 MT weapon, but Teller was a tad obsessed with these things so he might have. But as you increase yield you're mostly radiating more and more energy into space, rather than doing real damage with it - huge nukes are much less efficient than lots of "normal" nukes. Bang for buck, so to speak, is better for lots of small nukes. – StephenG Jan 11 '18 at 3:52
• If you want to kill all life (or most life) from Earth, the right way is a salted bomb. If you want to mostly destroy the Earth, though, that's several orders or magnitude bigger than we can actually muster right now. – Rekesoft Jan 11 '18 at 9:47

Atomic Rockets has some interesting information about nuclear weapons, including some rather alarming information about yields. Current nuclear weapons have yields in the range of 2-3 kt/kg, but it is possible to ramp up yield to something on the order of 11 kt/kg. At that range, it seems you could create a megaton weapon weighing only 90kg.

Calculating yields to weight can be looked at here

From there, the matter becomes "simple" (for some values of simple). You simply calculate the amount of energy needed to do something like stripping away a planet's atmosphere, then work backwards to determine the size of the bomb needed to generate that much energy. Since a fusion weapon of that size may be a bit impractical, you can also look up the "boom table" and see what sorts of other highly energetic events that could be employed:

1mg antimatter + matter = 43tons of TNT

1g at .9*c* = 29kt

Slamming a planet with a relativistic weapon (often referred as an RKKV [Relatavistic Kinetic Kill Vehicle]) is the usual SFnal way of doing things.

• I was going to add my own answer about kinetic weapons, but read your last paragraph just in time. I've +1ed you instead. :) – Tim B II Jan 11 '18 at 0:34

I'm going to approach this from a slightly different angle, while it may be possible to build a bomb big enough to do the damage required Murphy's answer suggests it would be very difficult to do so.

So what if instead you used smaller bombs strategically placed?
My initial thought was actually inspired by Doctor Who's Osterhagen Key which was supposed to destroy the whole planet with a series of carefully placed nukes, unfortunately DW is not known for it's scientific rigour so I'm not sure that is entirely possible.

What might work is to place some large nukes underground in the locations of super volcanoes around the world. Super volcano eruptions are thought to be connected to a number of Earth's biggest extinction events and according to this map (from this website):

There are 7 that we know of around the world. They don't really cover Europe, South America or Africa but the damage from 7 huge nuclear explosions and the subsequent tremendous volcanic activity should be enough to wipe out a significant percentage of life on Earth.

• Now you're starting to talk like a James Bond villain. – Neil Jan 11 '18 at 14:39
• From one of the least reliable news sources ever to "grace" the UK's stores : A story claiming North Korea is planning to set off the Yellowstone super volcano.. No need to make up a story when Fleet St. does it for you. :-) The original source for this is apparently one David Meade, who seems to be an exponent of a number of wild doomsday scenarios and extreme theories. – StephenG Jan 13 '18 at 5:04

# Yes

The good news is, this bomb is free! The bad news is you need about $1\times10^{28}$ J of energy to move it into a location where you can use it. The other good news is that this will definitely vaporize the Earth's oceans....and remove most of the crust too!

• Wouldn't it be easier to use the 1 x10^28 J of energy to destroy the Earth instead? – a4android Jan 11 '18 at 1:18
• @a4android A quick calculation showed that you can get at least a 4x return on your energy invested in energy out, so there is that. This answer was intended as reducto ad absurdum. If you really want to destroy the Earth, invest that energy in a large long-term comet, and you'll get an even higher relative return on your energy investment. – kingledion Jan 11 '18 at 1:23
• Thanks for providing the rationale. The reductio ad absurdum humour wasn't lost on me. Bigger bangs for the buck. – a4android Jan 11 '18 at 1:40
• A slightly more feasible version is changing the orbit of a large asteroid in retrograde orbit. With its own orbital speed plus the Earth orbital speed, you're looking at a 60km/s impact. That's an absurd amount of energy per ton of asteroid, for the comparatively tiny energy requirement of slightly changing its orbit. – Eth Jan 11 '18 at 15:38
• @Eth I agree. Halley's comet, for example, passed Earth with a relative velocity of 70 km/s. An object maybe 10 or 100 times the mass of Halley's comet would wipe out the Earth. – kingledion Jan 11 '18 at 16:08

# ...Maybe.

The largest nuclear weapon ever detonated was the Tsar Bomba. It was a fission-fusion-fission device which used layers to magnify the bombs power.

One implication of such a device is that you could scale such a device up further. There's some kind of a limit where above a certain size light from the first stage blows the later stages apart before they can actually ignite but nobody is quite sure exactly where that limit is.

It might be possible to build a bomb weighing many tens of thousands of tons with a yield in the range of of hundreds of gigatons.

Detonating such a device high in the air would be a bit pointless since the horizon sets a sort of limit: you end up just ejecting a chunk of the earths atmosphere within line of sight into space and a bigger bomb just means ejecting it faster.

but, for comparison the impact that wiped out the dinosaurs was on the order of 23,900 gigatons.

So a few hundred gigatons is definitely not enough to destroy all life on earth. And life is surprisingly durable, you'd need the kind of energy needed to liquefy much of the crust. Just for arguments sake lets guesstimate that you'd need something 100 times larger than the asteroid that killed the dinosaurs to kill every bug and critter on earth.

So lets round it off to 2,390,000 Gigatons needed.

lets assume you solve the problem of building an arbitrarily large nuclear weapon, you solve the problem of the early stages tearing apart the later stages and come up with a design that you can scale up smoothly.

The Tsar bomba design appears to have a limit of about 4 megatons per ton yield, you need to add 1 ton to the bomb design per 4 megatons of bomb yield.

So your world-killing bomb will need to weigh something like 597,500,000 tons.

At this point your evil mastermind would need to be buying large fractions of the entire worlds metal production and years worth of the entire worlds nuclear material production to get enough raw materials. It would be very very hard to be stealthy about it.

• Read the Atomic Rockets "Boom Table". It points out exactly how much energy is needed for stripping the atmosphere, boiling the oceans, removing the crust and other world ending events would need. projectrho.com/public_html/rocket/usefultables.php – Thucydides Jan 11 '18 at 16:14
• @Thucydides That table appears to be misleading. doing back of the envelope that appears to just be the number for the energy to accelerate the earths entire atmosphere to escape velocity (to within a fraction of a percent, 3.222×10^26 J vs 3.218×10^26 J ) . assuming you can impart that energy perfectly. ie: that there's no earths crust in the way. Detonate a bomb exactly that size and the atomosphere on the other side of the planet is staying firmly attached to earth. – Murphy Jan 12 '18 at 11:31
• To question the veracity of the table, you should contact the site admin of Atomic Rockets. Don't forget these numbers are the energy needed to perform the deed, and do not take into account efficiency, coupling mechanisms and so on. Think of these numbers as the amount of energy needed at the end of all the processes, and add in extra energy to account for inefficiencies and losses. – Thucydides Jan 13 '18 at 14:27

However... When humanity built the Large Hadron Collider, there were fears that it could create either a small black hole, or a strangelet.

The only reason it didn't happen was due to scale. It would take 39 times more energy than the LHC can provide to actually create a stable, world destroying black hole. I don't know about strangelets, but I think a larger collider would do the trick.

Should it happen, our planet would not be destroyed in a big, flash boom. It would collapse unto itself. I don't know how long it would take between a black hole/strangelet generation and the planetary collapse. It probably would not be immediate. But suffice to say, the black hole/strangelet would grow exponentially quicker and quicker. In the latter's case it would grow through a chain reaction.

Since you are the author of the story, that collapse could take as long as you like. Want it to disappear in a pop? That's fine for a SciFi setting. Would the ground break like in 2012 (the movie)? Would be very belieavable.

• There's the zero energy idea that the universe as we know it isn't truly at its lowest energy point since we can find energy even in a vacuum. Producing enough energy could be like punching a hole in the universe consequently wiping out all life in the universe, much less the Earth. If not that, there's always Ice Nine – Neil Jan 11 '18 at 14:42