What is the smallest possible nuke?

Factual Questions
1

As stated in the title, I’m curious about the smallest possible working nuclear weapon. The reason I ask is:

A Stephen King short story I sorta almost remember reading about 30 years ago. It was in a collection called “Night Shift” (I think), and the actual story may have been called “Toy Soldiers”. In the story, a guy received a package of army men. I assume it to have been comparable to the plastic army men many of us played with years ago…figures about 2 inches high or so, sculpted into various poses, with scaled vehicles and weapons. In King’s story, of course, the figures are alive, and attack the recipient. He’s fighting them off and holding his own…until all of a sudden he’s blown up in a massive (for the size of his opponents) explosion. The tag line at the end has a scrap of paper found in the box that says “NEW in this box, One (1) scale model thermo-nuclear device”.

I assume a weapon the size of the one mentioned in the spoiler box isn’t possible, but I wonder how small you could go. GI Joe size? Something that might kill everybody in an apartment but leave the building standing? Something that would take out a couple city blocks?

Note to the friendly Homeland Security folks: No, I’m not a terrorist. Just a sci-fi/horror/fantasy fan. I have no plans to engage in nuclear warfare on any scale.

2

You mean the SADM?

3

You can’t get much smaller than a suitcase nuke, because any smaller and you won’t have enough Plutonium to achieve critical mass.

4

The Master Speaks.

Rob

5

Wow…fast answers. Thanks guys. As a followup, what kind of damage would one of those mini-nukes…the SADM or suitcase model…do? I read the links about tons of TNT, but I don’t really know what that means. Are we talking wiping out a football field, city blocks, small town…

6

The closest “real” bomb is either a Daisy Cutter or the Russian FOAB. It looks like it could take out a single city block or so.

7

There’s also the M-388 Davy Crockett, a recoilless rifle firing a miniature nuclear warhead.

8

For a practical example: Some examples of 1KT bomb explosions.

I could see that taking out the better part of a city block, with lesser damage in a wider radius.

9

In theory you could make a very small nuke using californium; as the Wiki article mentions, it has a critical mass of 5 kilograms. I recall that way back when there was speculation about nuclear bullets. Nothing like that ever came to pass though, I expect that because californium is so incredibly expensive to make.

10

no comment

11

In the interest of nitpickery, the GBU-43 is more powerful than the BLU-82.

12

I saw that episode…and I remember get pissed because the mini mini nuke really wasnt to scale like the rest of the weapons…or at least that was my opinion.

You really have two questions.

How small can you make a nuclear weapon that still packs a hell of a whallop?

The simple answer is the infamous suitcase nuke as already mentioned.

If you are a terrorist, a blow the shit out of the enemy military thinker, or an efficient problem solver, the suitcase nuke (or snuke :slight_smile: for those in the know) is the answer you are interested in.

Got XYZ amount of uranium or plutonium? Usually makes sense to get as much bang as possible out of it.

To me, the more interesting question is this:

Can you make a subcritical nuke that still packs a hell of a whallop, but not nuclear level whallop?

Lets say your special forces, a couple of guys dressed in either black or aluminum foil (depends on the century), need to take out a bad guys facility. But, JUST that facility.

Now, a couple of those guys can only cary a hundred pounds or so of conventional bang. Might not be enough bang for the job. But on the other hand, a full blown nuke, even a snuke, is the equiv of thousands of TONS of conventional explosive.

Maybe your guys only need the equiv of a few thousand pounds of conventional bang.

Can you make a snuke that ONLY does that?

I’d say its possible, but ironically, I suspect it would actually be a bit harder to design and would be a bit heavier than a biggest bang possible snuke.

13

According to the Wiki article mentioned above, the Davy Crocket could yield as little as 10-20 tons up to 500 tons.

I’d still want to be on the other side of a big hill at the very least.

14

wuss, Indy only needed a lead lined fridge. :rolleyes:

15

The book “Project Orion” by George Dyson states that smaller devices than the Davy Crockett have been made. Ted Taylor, who did much of the development work for small fission devices in Los Alamos, is quoted as saying “…less that a kilogram. Quite bit less” when talking about minimum masses of plutonium that can be made to fission explosively.

Referring to the smallest bomb that had been produced, he said “It was a full implosion bomb that you could hold in one hand that was about six inches in diameter.” The yield of the thing wasn’t mentioned.

16

I find that very interesting!
Do they give ratio of yield to weight?

As in it weighed 1 kilogram but had the explosive yield of XYZ kilograms of conventional explosive?

17

Now we’re talking. An atomic handgrenade! Wonder if you could throw the thing far enough to not get caught in the kill zone?

Atomic Handgrenade would make an excellent band name…

18

No yield indicator at all IIRC. Project Orion was aimed at building spacecraft propelled by small nuclear explosions going off behind the craft. The smaller the bombs, the smoother the ride and the more of them you could pack into the thing.

Personally I was rather surprised they could be built so small, but if anyone should know, Ted Taylor should.

19

The fission primaries in modern thermonuclear ICBM warheads have to be small to fit inside the casing. See the W88 for an example.

I remember reading that the SADM was intentionally made larger and heavier than necessary so that it would require two people to deploy it.

20

Just for clarity, ans contrary to the title on the linked page, that video is not a nuclear or atomic bomb of any sort. That is film taken during Operation “Sailor Hat.” Sailor Hat was a series of weapons-effect tests that used large amounts of conventional explosives to test the survivability of warships to large shock waves. Each explosive charge was 500 tons of TNT or about half of a 1KT bomb.

On the page I linked, you can see photos of the beehive-shaped charge stacked on the shore of one of the Hawaiian Islands and the ships moored as test subjects.