Uranium Grenade: Can it exist, if so..why hasn't it been used?

[Elite Engineer]

Why use highly complex rocketry and satellite guidance? If a terrorist wanted to get the job done...well you get the picture.

 

 

I would think if this were somewhat feasible, it would have happened somewhere or at least been thought of.

 

So my question...is it possible?

 

~ee

[DrP]

Do you mean like a dirty bomb? I am hoping that as they keep such a tight restriction on who can get hold of Uranium that the security services would shut them down before they even make it.... lets hope anyway.

 

Also, they use Plutonium in bombs, Uranium is for power stations. You probably could make a dirty bomb with Uranium though I suppose.

Edited June 28, 2017 by DrP

[swansont]

The critical mass of uranium is several kilograms, and the subcritical masses that are combined have to be separated beforehand, so you have size constraints that preclude anything like a grenade. There are references to "suitcase bombs" which is closer to the appropriate size. But making something work is one task, and miniaturizing it is another. The latter introduces more technological hurdles in addition to the former.

[DrP]

I thought the 'dirty bombs' didn't need crit mass... they don't make nuclear explosions, rather they just fling a load of radioactive waste about, polluting the area. Although... how dangerous would a hand grenade sized lump of plutonium be if spread out by conventional explosion? Would be more of a pain in the arse with respect to clean up I suppose.

[swansont]

I thought the 'dirty bombs' didn't need crit mass... they don't make nuclear explosions, rather they just fling a load of radioactive waste about, polluting the area. Although... how dangerous would a hand grenade sized lump of plutonium be if spread out by conventional explosion? Would be more of a pain in the arse with respect to clean up I suppose.

 

 

The OP did not say anything about a dirty bomb. You probably wouldn't use uranium for a dirty bomb. (Hell, we use uranium in conventional projectiles) Plutonium would be worse, but still, you'd use something with a shorter half-life.

[DrP]

Yea - I think that is density related though. It makes for really heavy armour and bunker busting shells.

 

They have small hand held nukes in the film 'Starship Troopers' - I think they are fired from a grenade launcher or a bazooka or something like that. They are about the size of a bazooka shell tip. Fictional though. Loved the film!

[swansont]

Yea - I think that is density related though. It makes for really heavy armour and bunker busting shells.

Exactly the point of using it. Even though there have been long-term health issues associated with their use, contamination is not the motivation.

 

They have small hand held nukes in the film 'Starship Troopers' - I think they are fired from a grenade launcher or a bazooka or something like that. They are about the size of a bazooka shell tip. Fictional though. Loved the film!

And it's a work of fiction that uses several other scientific ideas of a dubious nature. It requires a pretty healthy suspension of disbelief in both science and military strategy/tactics

[DrP]

oh - totally! Great film though.. the nuke grenade just reminded me of it.

[Endy0816]

They made a few smaller ones, "Nuclear Grenades".

 

 

The article has more info:

https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)

 

Video of a test firing:

 

Pretty cool, not practical but cool.

Edited June 29, 2017 by Endy0816

[Elite Engineer]

ok, so grenade is not feasible...but why not use the storage space in a tractor trailer?

 

The point I'm trying to obtain is, why hasn't this been done yet? Is it theoretical constraints or logistical?

 

Also, not talking dirty bombs that have limited explosive impact...but a bomb with the explosive capabilities equal to that of Hiroshima or Nagasaki.

[Strange]

ok, so grenade is not feasible...but why not use the storage space in a tractor trailer?

 

 

I guess the military just think that planes or missiles are better delivery mechanisms than tractors. Go figure!

[DrP]

He is asking (from OP) why terrorists haven't built a small home made nuclear bomb yet.

 

1 - the materials you need are very restricted and are monitored.

2 - it is quite complex to make and get right.... I am not sure your average jihadi has that level of knowledge.

[StringJunky]

He is asking (from OP) why terrorists haven't built a small home made nuclear bomb yet.

 

1 - the materials you need are very restricted and are monitored.

2 - it is quite complex to make and get right.... I am not sure your average jihadi has that level of knowledge.

A quick Google suggests it is $10 000/g - that's a cheap, not 'normal' price, on the black market - so that's $120 000 000 for a critical mass of U-235; rather expensive. You've got the problem of safe assembly as well. You've got to acquire materials and build this covertly when most of the nuclear nations are very hot for monitoring for this activity. I think it boils down to the fact that you need to be an autonomous nation to realistically have the necessary resources to undertake something like thing this.

[Moontanman]

Is this what is being talked about! A hand grenade using the excited nucleus effect?

 

https://www.wired.com/2008/08/from-pseudoscie/

Edited June 29, 2017 by Moontanman

[swansont]

The mention of uranium and the context of the OP strongly imply a fission weapon was under discussion. Something that is already in use by the military.

[John Cuthber]

There are other isotopes with smaller critical masses (though not much)

https://en.wikipedia.org/wiki/Critical_mass#Critical_mass_of_a_bare_sphere

and these are even less accessible.

[Elite Engineer]

A quick Google suggests it is $10 000/g - that's a cheap, not 'normal' price, on the black market - so that's $120 000 000 for a critical mass of U-235; rather expensive. You've got the problem of safe assembly as well. You've got to acquire materials and build this covertly when most of the nuclear nations are very hot for monitoring for this activity. I think it boils down to the fact that you need to be an autonomous nation to realistically have the necessary resources to undertake something like thing this.

This was fantastic. Exactly what I wanted to find out. I had no idea uranium was that expensive.

He is asking (from OP) why terrorists haven't built a small home made nuclear bomb yet.

 

1 - the materials you need are very restricted and are monitored.

2 - it is quite complex to make and get right.... I am not sure your average jihadi has that level of knowledge.

Well this is why I asked the question. Sure it's "very restricted and monitored", but people steal all kinds of heavily guarded things. Also, the complexity of the device itself seems like a larger hurdle too.

[John Cuthber]

Fundamentally, this is an "odd" question.

I can, perhaps, throw a grenade 100 metres.

 

Do I want to be 100 metres from a nuclear explosion?

[Endy0816]

Conceivably a martyr could be willing enough, but I think the cost/benefit ratio isn't going to support it happening. Cost would be substantially higher while power is lower. Maybe a well protected target, even then probably easier routes.

 

Some areas do have radiation monitors. Not sure how effective they are though.

[Mordred]

Fundamentally, this is an "odd" question.

I can, perhaps, throw a grenade 100 metres.

 

Do I want to be 100 metres from a nuclear explosion?

If you have a death wish lol

[swansont]

Fundamentally, this is an "odd" question.

I can, perhaps, throw a grenade 100 metres.

 

Do I want to be 100 metres from a nuclear explosion?

 

 

 

Good point. That ties back to the issue of critical mass. With conventional explosives, you can vary the amount over some range. The minimum amount that will explode is quite small. But such fine-tuning is not feasible in a nuclear explosion. At best it would be exceedingly difficult to get an explosion that's just a few times bigger than a conventional explosive of similar size, and then you'd have a lot of unused nuclear material lying about to be scavenged.

[Carrock]

Good point. That ties back to the issue of critical mass. With conventional explosives, you can vary the amount over some range. The minimum amount that will explode is quite small. But such fine-tuning is not feasible in a nuclear explosion. At best it would be exceedingly difficult to get an explosion that's just a few times bigger than a conventional explosive of similar size, and then you'd have a lot of unused nuclear material lying about to be scavenged.

You can have an indefinitely small explosion e.g. accidentally bringing two subcritical hemispheres together.

The difficult part is normally maintaining a supercritical mass long enough for significant fission.

 

 

e.g. from https://en.wikipedia.org/wiki/Louis_Slotin

On 21 May 1946, Slotin was conducting a demonstration when he accidentally initiated a fission reaction, which released a burst of hard radiation. He received a lethal dose of radiation and died of acute radiation syndrome nine days later. Slotin was the second person to die from a criticality accident, following the death of Harry Daghlian, who had been exposed to radiation by the same core that killed Slotin....

Others were injured and may have died from nuclear related exposure some years later.

[John Cuthber]

Conceivably a martyr could be willing enough, but I think the cost/benefit ratio isn't going to support it happening. Cost would be substantially higher while power is lower. Maybe a well protected target, even then probably easier routes.

 

Some areas do have radiation monitors. Not sure how effective they are though.

A martyr could use a suitcase or a back pack (or even a car or truck).

And, if he didn't want to die, he could park the car + walk away.

So what use would a grenade ever be?

[swansont]

You can have an indefinitely small explosion e.g. accidentally bringing two subcritical hemispheres together.The difficult part is normally maintaining a supercritical mass long enough for significant fission.e.g. from https://en.wikipedia.org/wiki/Louis_Slotin

You can swallow explosives and die of poisoning, but that's not how the device was intended to work.

[Endy0816]

A martyr could use a suitcase or a back pack (or even a car or truck).

And, if he didn't want to die, he could park the car + walk away.

So what use would a grenade ever be?

I was really thinking a mechanically launched grenade against a protected target. Easy enough to monitor for people with backpacks or suspicious vehicles.

 

Sheer distance might be enough, but diving underwater is also fairly viable in many areas.