A while ago, I asked about what happens to a nuclear engine that gets smashed into the Moon. While not conclusively answered, it's likely that the contaminated area would be of significant size.

But what are the legal implications of doing this? Many international agreements deal with both the use of outer space, and also nuclear materials. The Moon treaty for instance says parties should take measures to prevent contamination of the environment, but it has a very weak international standing (18 parties, none of the US, Russia or China). Does some other piece of international law apply?


2 Answers 2


Principle 9 of the UN's Principles Relevant to the Use of Nuclear Power Sources In Outer Space says that whoever caused the debris field to happen must pay to clean up the mess.

  • 1
    $\begingroup$ How would one even clean up a Lunar debris field? $\endgroup$
    – ikrase
    Commented Nov 6, 2020 at 21:14
  • 2
    $\begingroup$ Let's hope we never have to try. $\endgroup$ Commented Nov 7, 2020 at 21:21
  • $\begingroup$ @ikrase Moon Roomba! $\endgroup$ Commented May 3, 2023 at 23:51
  • $\begingroup$ @JacobKrall Tricky, without an atmosphere. $\endgroup$ Commented May 4, 2023 at 15:53

The lunar surface gets quite cold during the two week long night, and while passive radioisotope thermal generators would come in handy for various lunar missions in several ways, they pose a challenge both because the radioisotopes are hard to license and obtain, and because launching radioactive material is unpopular and meets with varying amounts of resistance.

Having a source of "hot" radioisotopes already present not only in space but in (relatively) concentrated amounts in places offers a great opportunity for space miners to collect and robotically process and then encapsulate it in ceramic made from lunar regolith.

While Andy Griffith is mostly known for one or two roles (the Sherif and the detective) he's played both a self-centered, narcissistic political operative and junk collector traveling to the Moon to strike it rich!

So after crashing a nuclear rocket into the Moon one might argue that they are doing future Lunar explorers a favor! They could argue that they have landed critical and difficult to launch supplies on the Moon for the benefit of humanity; that they've done it a service!

screenshot from "Forgotten TV: Andy Griffith's Salvage-1"

  • 5
    $\begingroup$ Random fission reactor daughter isotopes aren't exactly ideal RTG ingredients. Otherwise, we'd just use reactor waste to make RTGs instead of using expensive stuff like Pu-238. We use relatively benign alpha emitters for RTGs, not stuff that emits high energy beta and gamma radiation. $\endgroup$
    – PM 2Ring
    Commented Dec 18, 2021 at 9:37
  • $\begingroup$ @PM2Ring that is of course correct which is why the "robotically process" step I mentioned would necessitate some nasty separation steps. Among all the isotopes present there must be some alpha emitters with low rates of beta, gamma and fission neutrons. Remember this is primarily an excuse, an explanation why crashing and making a mess was a good thing. They don't necessarily have to do the cleanup, only say that they've done future Moon explorers a favor by making some alpha emitters available. Basically I had "Salvage 1" burning a hole in my pocket and needed to post it somewhere. :-) $\endgroup$
    – uhoh
    Commented Dec 18, 2021 at 21:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.