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Terrorists gain complete control of the world's nuclear weapons and they want to destroy the moon. Could they do this with ICBMs? If not, is there enough power in the arsenal to destroy the moon if they could somehow transport the weapons to the moon's surface?

If this is totally impossible, could a weapon strong enough to do it be created with the current level of technology of humans?

Edit: Just to clarify, the goal of these terrorists is not necessarily to kill anyone on Earth. They simply don't like the moon. Additionally, "destroy" in this case means to break the moon apart into pieces. Ideally the big pieces would not fall down on Earth in a cataclysmic way, but it is fine with these terrorists if they recombine into the moon in a few centuries due to gravitational forces.

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    $\begingroup$ No, it is impossible. Our nukes could not destroy the moon it is too large. $\endgroup$ – Bellerophon Sep 1 '16 at 20:40
  • $\begingroup$ With a good arrangement of nukes we could turn the surface of the Moon to a desert, just as we can do with the Earth. Anyway, since the Moon is already a desert it would hardly qualify as destroying it. $\endgroup$ – Pere Sep 1 '16 at 20:47
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    $\begingroup$ I fully support your war on the Moon. Alas, the deepest hole we've ever drilled is 7.6 miles, a single borehole in Russia. The moon is 2,000 miles in diameter. $\endgroup$ – Xplodotron Sep 1 '16 at 21:03
  • $\begingroup$ Relevant meta discussion: space is big $\endgroup$ – Azuaron Sep 2 '16 at 12:53
  • $\begingroup$ Since the beginning of time, man has yearned to destroy the moon. $\endgroup$ – userLTK Jul 16 '18 at 21:19
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No, current ICBMs cannot reach the moon. They're very much optimised for putting their payloads not quite into orbit, and getting to the moon requires quite a bit more speed. The space launchers around that are derived from ICBMs were designed when nuclear weapons were much larger and heavier.

If you transported all of our nuclear weapons to the moon and detonated them, you could not destroy the moon. It is simply loo large. The bits you would blast off it while trying will do a lot of damage to Earth, but you might as well save yourself the effort and nuke Earth directly.

Is it possible to build (a) weapon(s) with sufficient power to destroy the moon? Well, that depends what you mean by "destroy".

  1. Building enough nukes to shatter it and give the pieces enough speed that it won't settle back together under the pieces' mutual gravity will probably require more uranium than is available in Earth's crust. And if you do it, you'll kill everyone on Earth, which you can do far more easily than this project.

  2. If you get much more ambitious than that, it still doesn't work. You can't evaporate it to gas with radiation from nuclear explosions without also evaporating several miles off the Earth's crust, and once again, you can kill everyone on Earth with far less effort than that.

  3. Edit: They may only want to shatter it into smaller moons, but if by some miracle those all remain in orbit round Earth, with none of them hitting Earth immediately, they will perturb each other's orbits. There's no way of predicting just what will happen, because the n-body problem is unstable. Some of them may be ejected from the immediate area of the Earth and become dwarf planets, some may hit the Earth, and most of the rest will recombine into a single body within, probably, a couple of years.

In terms of our ability to make changes to the Earth and Moon, in terms of reshaping or shattering them, think of us as lichen growing on the surface of a statue. Except less capable: lichen can eat away at a statue over centuries. We can't manage that much.

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  • $\begingroup$ If I recall the specific location correctly, it is the Outer Space Treaty that also specifically prohibits putting any kind of weapon system in orbit. The USSR did have orbit-capable nuclear delivery vehicles in the 1980s, which were dismantled in response to treaty changes prohibiting orbital (as opposed to suborbital) flight of weapon systems. $\endgroup$ – a CVn Sep 1 '16 at 21:08
  • $\begingroup$ I agree with one caveat. Unless you bury the nukes, you won't have big chunks of Moon. There's little to know air on the Moon so there wouldn't be any big pressure wave. You might vaporize a bunch of it and the Earth may drift through a fog bank of rock steam but that should be no worse than a good sized volcanic eruption on the Earth. $\endgroup$ – ShadoCat Feb 1 '18 at 23:36
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The statement "Destroy the Moon" is a rather broad one, all things considered, but like the top answer of this related question, I shall assume you mean to completely and utterly obliterate the moon from existence, rather than just fracture it or something less cataclysmic.

In order to obliterate a planetary body, we must first know how much energy is required. Luckily, there is a convenient value known as the Gravitational Binding Energy which tells us how much energy it would take to blow a massive body apart (that's not really what it was designed to do, but hey, science).

So what is the Gravitational Binding Energy of the Moon? Using the formula:

enter image description here

where G is the Gravitational Constant, M is the mass of the body, and R is the radius of the body, we can simply plug in numbers and see what we get.

It turns out the Gravitational Binding Energy of the Moon is 1.24E27 Joules (or 1,240,000,000,000,000,000,000,000,000 J). To put that into perspective (if that is even possible), the Tsar Bomba, the largest nuclear weapon ever detonated, had a yield around 10^17 Joules, meaning we would need about 10 Trillion Tsar Bombas to obliterate the moon. Needless to say, we don't have that many. Even the total energy stored in the Earth's fossil fuels is estimated to be only 10^22 Joules, so we're need another 10,000 Earth's to mine enough natural gas, oil, and coal to do the job.

Even if all that was desired was a significant fracture in the moon, we would still need energy beyond what we can generate. The 2004 Indian Ocean Earthquake (~9.2 on the Richter Scale) released approximately 10^22. An Earthquake (moonquake?) powerful enough to crack the entire moon would need to be several orders of magnitude more powerful (probably in the 10^25 to 10^26 Joules range).

So I guess the answer to your question is: Nope.

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  • $\begingroup$ An excellent Wikipedia article here is a fun read if you want a better idea how much energy is being used. $\endgroup$ – MozerShmozer Sep 1 '16 at 21:17
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MozerShmozer quantified the answer, so using the Atomic Rockets "Boom Table" we see the energy needed to overcome the gravitational binding energy of the Moon is somewhat higher than needed to heat the Earth's oceans to boiling. That really puts things into perspective.

However, we are only one AU away from a really powerful energy source, which releases 3.9X 10^26J of energy each second. If we could tap a significant fraction of that, then we might be able to have a bit of planetary engineering fun.

On NextBigFuture, a guest post was published speculating on a possible solution to the puzzle of "Tabby's Star". The author suggested that a massive mirror system orbiting the star was used to direct beams of sunlight to power giant solar sails on interstellar missions (or used as an optical telescope of unusual size). The amount of energy that a mirror the size of the Moon's orbit could reflect is simply mind boggling, and if this light beam were to be focused on the Earth's Moon, it could rapidly vaporize the Moon. (The author also makes a few assumptions, but if they are correct the aliens around Tabby's star could potentially vapourize the Earth from 1500 light years away!)

enter image description here

With a bit of tweaking, the illuminated side of the Moon could be vaporized to create an impromptu rocket motor, and the Moon sent off into space. The obligatory XKCD comic is here.

enter image description here

So nuclear weapons are not going to cut it, but some far future terrorists might be able to hijack a solar mirror to do the deed.

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Current technology: yes. Not how you are envisioning it, though.

As others have shown the moon would laugh at the world's arsenal, even anything we could reasonably build.

However, there's another approach, albeit far beyond the capabilities of those terrorists. (Not a show-stopper, though--they have the arsenal, they could demand the world do it or they use those missiles.) You launch a nuclear reactor, mining equipment and some factories and land them on the moon. The reactor provides your initial power, the factories turn out solar cells and once things are up and going, mass drivers. While this would make Apollo look like very small potatoes it's not beyond current technology.

The solar cells power the mass drivers, bits of moon are shot off at very high speed whenever the drivers are properly aligned. They are spread around the moon so the thrust is even. Slowly the moon's orbit increases, it eventually departs. If that's not good enough for them it can be guided to an impact with Mars or Venus.

Note that the terrorists will not live to see this happen. They probably won't even live to see any change in it's orbit.

(For those who will say it's too big: The factories keep churning out cells and drivers. The thrust keeps growing and has a huge amount of time to apply it. It's very slow but there's no limit, it will just keep going and eventually leave.)

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Terrorists gain complete control of the world's nuclear weapons and they want to destroy the moon. Could they do this with ICBMs?

No. They do not have the delta-vee to reach the Moon (or even achieve low earth orbit).

If not, is there enough power in the arsenal to destroy the moon if they could somehow transport the weapons to the moon's surface?

Nope, again. The current Earth arsenal falls short by many orders of magnitude. Even magicking the warheads on the Moon and using them as Orion propulsors is not going to significantly affect the Moon at all.

Most of the adverse effects nuclear warheads have on Earth are due to indirect effects: fires, nuclear winter, radioactive contamination. This is of no matter as far as the Moon's destruction is concerned.

If this is totally impossible, could a weapon strong enough to do it be created with the current level of technology of humans?

Not really.

We need energy - lots of energy. We do not have that much energy. We need to take that energy wherever it is, and on Earth there's not enough energy in fossil fuel form, while radioactive ores cannot currently be mined to that extent (you'd need to tap the Earth's core).

So we're left with the Sun and with the gravitational potential energy of solar bodies. Solar sails, and kinetic impactors.

We could make a significant effort, which would have to last several centuries, and use railguns and solar sails to place a sizeable asteroid on a collision course with the Moon. This happens in Bob Shaw's The Ceres Solution.

The impact might fragment the moon (and ensure a meteorite shower to dwarf the Chicxulub Event), but it would require a body with a considerable fraction of the Moon's mass, and at that point it would begin to become more convenient to do the same operations on the Moon instead. It would be much easier to reach, and way safer to slowly pull the Moon towards Sun-Earth Lagrange 1 point.

There is at least one novel featuring a comet-triggered fragmentation, but again, the comet would need to travel at relativistic speeds (within a few thousandths of percent from c) and be unbelievably dense. Not even osmium is dense enough; at those speeds, a rough estimate of the penetrative power of a projectile is given by Newton's formula. Pump more energy in the impactor and all you get is a massive explosion without penetration (I was a bit taken aback by the last Starfire novel for this reason).

We could use some handwavium to decrease the Moon's density and have it made up of loose rubble, but keep in mind that this doesn't really work: with that mass, the rubble would collapse into a compact sphere under its own weight, and the lunar seismology (and density, and mascon distribution) is roughly known since the Apollo years.

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