# Thorium bomb **URL:** \ **Category:** Factual Questions\ **Created:** [October 3, 2023, 4:36am UTC](https://boards.straightdope.com/t/thorium-bomb/991037 "2023-10-03T04:36:06Z")\ **Posts on this page:** 15\ **Page:** 2
**Author:** ![Babale](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/babale/32/15666_2.png) [@Babale](https://boards.straightdope.com/u/Babale)\ **Post date:** [October 5, 2023, 2:50am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/21 "2023-10-05T02:50:57Z")
> [@EnolaStraight](#): > > He 2 is “regular” helium with 2 protons and 2 neutrons, right? The number is the total atomic mass. Helium 2 is 2 protons. Helium 3 is 2 protons and a neutron. Regular helium is Helium 4. By far the most abundant, over helium 3 (one proton). > [@EnolaStraight](#): > > I take it a 2 proton **one** neutron nucleus cannot be a thing. That’s Helium 3, it’s rare but it exists. A diproton is Helium 2. It’s extremely unstable and doesn’t hang around. (We assume it exists _during_ fusion). ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [October 5, 2023, 1:25pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/22 "2023-10-05T13:25:36Z")
> [@Babale](#): > > That’s Helium 3, it’s rare but it exists. Relative to the amount of boring old He-4, rare. > **[Helium-3 | Natural abundance](https://en.wikipedia.org/wiki/Helium-3#Natural_abundance)** > > 3He is a primordial substance in the Earth's mantle, considered to have become entrapped in the Earth during planetary formation. The ratio of 3He to 4He within the Earth's crust and mantle is less than that for assumptions of solar disk composition as obtained from meteorite and lunar samples, with terrestrial materials generally containing lower 3He/4He ratios due to ingrowth of 4He from radioactive decay. > 3He has a cosmological ratio of 300 atoms per million atoms of 4He (at. ppm), leading to... ---
**Author:** ![zimaane](https://avatars.discourse-cdn.com/v4/letter/z/a3d4f5/32.png) [@zimaane](https://boards.straightdope.com/u/zimaane)\ **Post date:** [October 5, 2023, 4:05pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/23 "2023-10-05T16:05:01Z")
He - 3 may be more common on the surface of the moon, due to deposition from the solar wind. People have speculated that He - 3 could be mined on the moon and used in fusion reactors. As of now it’s a rather far fetched idea, but it’s not totally absurd. ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [October 5, 2023, 8:22pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/24 "2023-10-05T20:22:35Z")
> [@Chronos](#): > > Really, to make the diproton stable, you’d need to completely change the nature of the Strong Force. It’s not just “make the Strong Force stronger than the electromagnetic, so they stick together”: Remember, the dineutron also doesn’t hold together, and it’s the Strong Force that blows it apart To add to @Chronos’s point: How strongly attracted single neutrons and/or protons are to one another depends on the quantum mechanical spin of the two particles. All three pairings (nn, pp, np) are unstable in the case that the nucleon spins are anti-parallel. So for the deuteron (np), the neutron and proton always have parallel spins. So, why doesn’t this lead to comparable nn and pp bound states? The problem is that these involve identical particles and thus they run afoul of the [Pauli exclusion principle](https://en.wikipedia.org/wiki/Pauli_exclusion_principle). The nuclear force requires the spins to be parallel to have a potentially bound state, but the exclusion principle doesn’t allow identical particles to occupy the same state, which means that spatial overlap (which is part of the quantum state) is disfavored in the parallel-spin nn and pp cases. So, the np case is the uniquely bound case because the neutron and proton can have the same spin without penalty. ---
**Author:** ![IridiumIodineSulfur](https://avatars.discourse-cdn.com/v4/letter/i/b9e5f3/32.png) [@IridiumIodineSulfur](https://boards.straightdope.com/u/IridiumIodineSulfur)\ **Post date:** [July 9, 2025, 9:44pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/25 "2025-07-09T21:44:36Z")
Uranium is pretty cheap and accessible. Whether or not thorium can be used, uranium is very easy to get. They also make plutonium bombs and I once wondered why they didn’t use neptunium and other actinides. The answer is, for at least neptunium, it’s not easy to acquire. Thorium seems to be similar in that sense. ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [July 10, 2025, 5:00am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/26 "2025-07-10T05:00:19Z")
Previous thread on neptunium’s bomb-making capacity: [Neptunium doesn’t have an explosive personality?](https://boards.straightdope.com/t/neptunium-doesnt-have-an-explosive-personality/835371) ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [August 21, 2025, 1:08pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/27 "2025-08-21T13:08:27Z")
Here’s a resource that’s pretty good. AFAIK the physics is good, even if the articles themselves are a little long in the tooth, as that stuff doesn’t really change fast these days. [Nuclear Materials](https://nuclearweaponarchive.org/Nwfaq/Nfaq6.html) and a broader set of nuclear weapons topics. [The Nuclear Weapon Archive - A Guide to Nuclear Weapons](https://nuclearweaponarchive.org/) ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [August 28, 2025, 12:02am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/28 "2025-08-28T00:02:06Z")
> [@IridiumIodineSulfur](#): > > The answer is, for at least neptunium, it’s not easy to acquire. Thorium seems to be similar in that sense. I thought one of the advantages of thorium is that it is abundant. Waaaay more abundant than uranium. Very easy to access. > Thorium is a naturally-occurring, slightly radioactive metal discovered in 1828 by the Swedish chemist Jons Jakob Berzelius, who named it after Thor, the Norse god of thunder. It is found in small amounts in most rocks and soils, where it is about three times more abundant than uranium. Soil contains an average of around 6 parts per million (ppm) of thorium. Thorium is very insoluble, which is why it is plentiful in sands but not in seawater, in contrast to uranium. - [SOURCE](https://world-nuclear.org/information-library/current-and-future-generation/thorium#:~:text=It%2520is%2520found%2520in%2520small,seawater%252C%2520in%2520contrast%2520to%2520uranium.) ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [August 28, 2025, 3:28am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/29 "2025-08-28T03:28:26Z")
Acquiring thorium for power production may be attractive if the price of uranium goes up. However, if you are trying to build a _bomb_, is a slight difference in the cost of ore your primary consideration? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 29, 2025, 1:18am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/30 "2025-08-29T01:18:10Z")
For any sort of nuclear context, what’s relevant is never how easy it is to get the element. It’s how easy it is to get the appropriate isotope of the element. ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [August 30, 2025, 4:33am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/31 "2025-08-30T04:33:33Z")
You’re gonna mess up the world using heavy radioactive elements, explosive or not. Creating fine-powder (i.e. “weapnised”) and mailing it, air dropping Anthrax (hard to make - how much you got?) from unmarled plames is the way to go. ETA: last week the police or some LEO’s in NYC received envelopes filled with white powder. it was Boric Acid which is poisonous (to insects0 If it were high quality Anthrax powder even looking upon white powder may have led to their demise. ---
**Author:** ![IridiumIodineSulfur](https://avatars.discourse-cdn.com/v4/letter/i/b9e5f3/32.png) [@IridiumIodineSulfur](https://boards.straightdope.com/u/IridiumIodineSulfur)\ **Post date:** [September 17, 2025, 1:57am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/32 "2025-09-17T01:57:52Z")
Oh, neat! I don’t see why it couldn’t be used, in that case. Despite any physical properties I don’t know about, I assume somewhere in the process of making it it costs more. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [September 17, 2025, 9:00pm UTC](https://boards.straightdope.com/t/thorium-bomb/991037/33 "2025-09-17T21:00:05Z")
Not all radioactive isotopes are fissionable. Most aren’t, in fact. ---
**Author:** ![Ancient\_Nerd](https://avatars.discourse-cdn.com/v4/letter/a/ed655f/32.png) [@Ancient\_Nerd](https://boards.straightdope.com/u/Ancient_Nerd)\ **Post date:** [September 19, 2025, 5:56am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/34 "2025-09-19T05:56:10Z")
It would take two steps for the thorium to turn into uranium. Thorium 233 decays into protactinium 233 with a half-life of 21.83 minutes. Then protactinium decays into uranium 233 with a half-life of 26.975 days. It works for a nuclear reactor, but not for a bomb. ---
**Author:** ![Ancient\_Nerd](https://avatars.discourse-cdn.com/v4/letter/a/ed655f/32.png) [@Ancient\_Nerd](https://boards.straightdope.com/u/Ancient_Nerd)\ **Post date:** [September 19, 2025, 6:34am UTC](https://boards.straightdope.com/t/thorium-bomb/991037/35 "2025-09-19T06:34:03Z")
> [@Chronos](#): > > For any sort of nuclear context, what’s relevant is never how easy it is to get the element. It’s how easy it is to get the appropriate isotope of the element. [https://www.nndc.bnl.gov/nudat3/](https://www.nndc.bnl.gov/nudat3/) 99.98% of naturally occurring Thorium is 232 Th, the one you want. [Previous page](https://boards.straightdope.com/t/thorium-bomb/991037.md?page=1)