228

Let's try to do this. (They told you it can't be done. They're right. Realistically, it can't. So, disclaimer: I'm going to employ industrial quantities of high-grade Improbability). Notes I had to play with "realize what this thing is". There's no reasonable way I can hand-wave an alchemist deducing nuclear fission. The best I think we can aim for is ...


76

For your reference: some years ago in Brazil a scrap thief, while salvaging through the remnants of a hospital, found a piece of material which emitted a nice glowing blue light. He was smart enough to think "wow, this will make a pretty good gift for my wife", and tried to take it with him. Long story short: 4 dead and various contaminated from a piece of ...


74

The crucial question is what they do with it. As a museum piece, it's not really dangerous. If they open it up, bad things can happen. This answer assumes that we're talking about a two-stage thermonuclear device. This has a couple of main components: a primary fission charge, a secondary fission and fusion charge, an interstage, and a tamper. The primary ...


64

Why not? Make it a relatively dumb bomb on a timer, paint it black, give it radar absorbent plating, and (this is the important part) launch it from the far side of Earth. Your delivery system can be whatever you want - mass driver, rockets, whatever - just make sure that all the thermal bloom associated with an atmospheric launch happens on the far side ...


52

The meteorite started the war. The country hit by the meteorite considered the impact an indirect attack by the nations that did not warn them. For example; foreign space agencies collectively refused to inform Pakistan of the meteorite about to hit them. Pakistan is justifiably angry at every space faring nation, particularly India due to past conflicts. ...


50

The true answer to your question can be found on a place called Anthrax Island in Scotland. In 1942, British Military scientists experimented with various strains of anthrax to use as biological weapons during World War II. They bombed the small island with a particularly virulent strain of anthrax called Vollum 14578. One of the reasons why anthrax didn't ...


48

No, on a variety of fronts So, first of all, there's no nuclear warhead ever developed that will last six hundred years, for a variety of reasons: High explosives (required as the triggering device for the nuclear weapon) degrade quickly, even when stabilized versions are used. RDX (the C-family of explosives) has a recommended shelf life of five years. ...


39

The US considered demonstrating the devastating effect of an atomic bomb before attacking Japan in an attempt to convince the Japanese to surrender without massive civilian casualties. They concluded that they could propose no technical demonstration likely to bring an end to the war. For the same reasons that the US didn't announce the existence of nuclear ...


39

TLDR Earlier non-proliferation treaty 1950: Korean War On 25 June 1950, North Korea invades South Korea. The United States give them an ultimatum: go back north, or they will suffer the same fate as Hiroshima and Nagazaki. The North Koreans refuse, thinking that the USA would never do this, as North Korea has two powerful allies: the Soviet Union and ...


38

I admit up front, that my first reaction was to consider the comedy potential of this situation, as the device might have labels on it. That would make a big difference - think of the warnings on a bag of peanuts or a chainsaw, and enjoy imagination ("warning: this product may destroy large cities.", "user safety information: this product can cause cancers."...


36

Make your own, Sorcerers Apprentice style Pickup truck, guns, ammo, food, radiation suit, 10 7kg Uranium bricks.(Federal government allows you to get 7kg at a time and possess no more than 70 in a calendar year reputable sources may do sales checks and block your shenanigans) Set this up outside a flooded quarry. Set up pumps to drain the quarry. As ...


34

There are lot of neutron sources: https://en.wikipedia.org/wiki/Neutron_source Not all of them is useful for large scale transmutation since their neutron flux is many orders of magnitude smaller than that of nuclear reactors. However, spallation neutron sources have higher flux than reactors and don't require radioisotopes (They are high energy particle ...


34

They would have no idea whatsoever about what they were dealing with. None. Zero, nada, zilch. Some time later than the Middle Ages, people would start to recognize the conventional explosives, though the first modern-looking explosives didn't appear until the late 19th century. People wouldn't have a clue what the core was until post WWII. There are ...


30

This is just to add some more details to jdunlop's answer. I have done something like that quite a few times in Kerbal Space Program. Not because I wanted to bombard the game's equivalent to our Moon, but because I am cheap. Some missions require you to gather data from a certain altitude from the Mün's surface, but don't say anything about soft landing or ...


30

Yes and no. An asteroid, or any impact really, cannot set off thermonuclear warheads, in the sense of causing a nuclear blast. These warheads are composed of disks of conventional explosives that have to go off in an extremely precise manner in order to achieve a proper nuclear detonation. If that doesn't occur - if they go off in any other configuration - ...


30

You have three sources of risk: radiological. This is probably negligible, because after 500 years anything with a half-life shorter than 50 years is gone. The shielding on the other hand is pretty stable. explosive. Nuclear warheads have an explosive primer, containing a sizeable quantity of explosive compounds. Some of these might have become inert, some ...


29

There are a lot of alternatives to nuclear weapons which are not explored in movies because the choice would be rather anticlimactic. Remember that these movies rarely make any sense; it's all about shock and awe, not logic. Consider that a flesh and blood creature is going to be severely damaged by an explosion in real life, unlike movie monsters which are ...


27

Not really. To understand how a nuclear weapon works, they would need an understanding of nuclear physics. That is 20th century science, and even an "inspired" medieval thinker would be unable to get the experimental data to refine this theory. The weapon also contains electronics. Understanding those would require a practical understanding of electricity,...


27

Yes, it is theoretically possible. (nuclear) bombs do not look at flags or landmarks, they don't know if they are exploding in a friendly territory or not. They are just given some coordinates, their computer follows the trajectory from the launch point until the target point and then, KABOOOM, they explode. If somebody, accidentally or willingly, would ...


27

The kinetic energy of a bullet (for non relativistic speeds) is given by the known formula $E_K = 1/2 m v^2$. For a velocity of $150 \ \text{km}/\text{s}$ you need about $100 \ \text{kg}$ to deliver 1 Kton ($4 \cdot 10^{12} \ \text J$) of kinetic energy. Apparently then you can double the delivered energy by strapping a nuke to the bullet. But... As in ...


26

Don't use an ICBM. Use an ASAT with a nuke as payload. These things have existed for decades. Anti-satellite weapons (ASAT) are space weapons designed to incapacitate or destroy satellites for strategic military purposes. Several nations possess operational ASAT systems, with others in development or design. Although no ASAT system has yet been utilised ...


24

Flood a democratic country with nuclear weapons with clones. Make sure each clone gets to be registered as an elector. Candidate the master as president (or prime minister), and have the clones vote for him. Sure victory. Once he is in the war room with access to the nuclear suitcase, let him fire it with no mercy. Wait for retaliation.


23

No, and we thought they were (kinda) close to one The Germans probably could have made a bomb if they hadn't gotten caught up on the whole "heavy water" thing. In fact, Einstein warning FDR about German bomb efforts in his letter was part of what prompted the Manhattan project. Late in the war, the Germans tried to send the Japanese the Uranium they had, ...


20

Oh my... This has happened before. It wasn't a bomb, though. It was 1987. A hospital in a Brazillian town used caesium-137, which is radioactive, in a radiotherapy machine. The hospital building was abandoned with the equipment in it. Some thieves scavenged the caesium containing equipment. They pried their salvage open and found an eerily beautiful blue-...


19

ICBM is a bad pick. It can't track or be guided from the ground. You don't expect an enemy city to start running. I doubt, an alien ship will stand in place and wait for minutes for us to hit it. They would need to adjust the guidance system and give it ability to track targets. How fast they can do that? Military will not tell me. It will be days, weeks ...


18

I won't expand on the math done by L.Dutch as it's correct and speaks for itself, however I would advise against the use of nukes in space for a few reasons: Cost Not only would you have to figure out the design aspects of the weapon, but you'd also be throwing expensive material away with each shot, if you had to choose in a war zone between throwing an ...


17

Somewhat realistic. Use a Cobalt Bomb. For a realistic dirty bomb that has a has a 50 year minimum, city-sized lethality, where "realistic" is assumed to be a combination of cost-effectiveness and technological/military feasibility rather than political tenability, you'd want a Cobalt Bomb. As defined by Wikipedia: a cobalt bomb is a type of "salted ...


17

Honestly, nuclear weapons (or American nuclear weapons, at least), have robust and effective safeguards to prevent a nuke from accidentally going off for technical reasons (like an electrical short in the triggering mechanism or being hit by gunfire or an explosion, or being set on fire, etc.), and are designed to be exceedingly hard to detonate anyway. The ...


17

The first soviet nuke was detonated on 29th August 1949. If in the 4 years between the nuking of Nagasaki (9th August 1945) and that date the US would have struck first, nuking Moscow and wiping out the Soviet leadership, it could have resulted in no MAD, as one of two sides would have not developed.


17

No. The concept of a fission explosion had been theorized for some time. The issue was - it would cost a fortune to find out if it would actually work, given the technology of that age. In the 1920's and 1930's, radiation science was still emerging, and most people working with radiation were pursuing peaceful uses, so the idea of an uncontrolled chain ...


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