The outer space treaty prohibits putting weapons of mass destruction into orbit.
But - if the intention is not to destroy people, it's not really a weapon of mass destruction. Just from the timing, just a few days later, I am guessing you are thinking about using nukes to terraform Mars.
That's a bit like using nukes to deflect an asteroid. Which - I'm no lawyer, just suggesting this, but especially if it was a collaborative international effort, it's not being used as a weapon of mass destruction, because of the intent. Unlike the partial nuclear test ban treaty which is specifically about nuclear weapons.
It would be undoubtedly nuclear - and undoubtedly capable of mass destruction - but is it a weapon if the intent is to drop it on the poles of Mars for terraforming - or to deflect an asteroid?
I think we would need an expert on space law to step in here to clarify that one - or if anyone knows of an article on this by an expert on space law?...
In any case if it was needed to deflect an asteroid (very unlikely low probability thing despite the movies as there are much gentler ways to deflect asteroids given more time) - I'm sure that one way or another would be found to make it legally acceptable, some kind of temporary waiver or something as everyone would be agreed on.
And if everyone agreed internationally on the benefits from an attempt to terraform Mars, surely the same.
But you'd need to make sure that everyone understood the intent :).
Then - the main other thing in the OST is whether you are interfering in the activities of other parties to the treaty. If you drop a nuke on the poles, and someone else in the treaty wants to study some geological formation at the poles, or to study life forms that only exist there if we find such (there's a possibility of seasonal small amounts of liquid water for instance in Richardson crater through the solid state greenhouse effect) that would surely count as interfering with their investigation. Same also if you do it to warm up the planet, and there isn't international agreement to warm the planet.
The relevant article here is - the bits to do with interfering with other parties to the treaty in bold:
But your settlers anyway would need international agreement there also, on whether or not settling Mars interferes or helps with scientific investigation of the planet.
But anyway - nukes won't do the trick. It was just a half joking "off the cuff" remark. There were many news stories that tried to develop it into a fully worked out plan to terraform Mars. But all he says in the interview, in a joking context and tone of voice, is "The fast way is to drop thermonuclear weapons on the poles". That's not a plan. When he has a plan he unveils it in full detail as for hyperloop.
There is no published paper either to back up that idea, at least I can't find one and none of the stories about it mention one. It's just an off the cuff remark in conversation.
If you look into it some more, it is clear that nukes are nowhere near powerful enough to change the climate of Mars. I worked out that the Tsar Bomba, largest nuke ever built, would be nowhere near as powerful as comet impacts, which happen naturally. You'd need 625,000 Tsar Bombas to equal one comet impact. And they are nowhere near enough to jolt Mars into a new climate equilibrium as they haven't done it yet.
You can also do it another way. By working out the energy needed just to melt ice (ignoring need to raise it to melting point first) and if all the energy from the blast went into melting water, you'd melt enough for a 4.3 micron layer over the surface of Mars with each Tsar Bomba explosion. But of course it wouldn't all go into melting, only a tiny fraction, and the water once melted would freeze over quickly and not much get into the atmosphere. And as for dry ice, it could only liberate 0005% of the current Mars atmosphere - and to tip it into a new greenhouse state, it has to liberate enough for ten times the Mars atmosphere. So, in total - it is just many orders of magnitude too puny to change the Mars atmosphere. Even if that much CO2 existed on Mars, which isn't certain (only a tenth of it found so far) there just isn't enough energy to liberate it unless you can drop many millions, and given that this is a big over estimate of its effect, more likely many billions, of Tsar Bombas on Mars.
Some water vapour and CO2 would be liberated but it would soon condense back to the poles, even if you let off thousands of Tsar Bombas on Mars.
For details, see Why Nukes Can't Terraform Mars - Pack Less Punch Than A Comet Collision
"Article IV
"States Parties to the Treaty undertake not to place in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner.
"The Moon and other celestial bodies shall be used by all States Parties to the Treaty exclusively for peaceful purposes. The establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military maneuvers on celestial bodies shall be forbidden. The use of military personnel for scientific research or for any other peaceful purposes shall not be prohibited. The use of any equipment or facility necessary for peaceful exploration of the Moon and other celestial bodies shall also not be prohibited."
But - if the intention is not to destroy people, it's not really a weapon of mass destruction. Just from the timing, just a few days later, I am guessing you are thinking about using nukes to terraform Mars.
IS IT A NUCLEAR WEAPON IF NOT INTENDED FOR HARM?
That's a bit like using nukes to deflect an asteroid. Which - I'm no lawyer, just suggesting this, but especially if it was a collaborative international effort, it's not being used as a weapon of mass destruction, because of the intent. Unlike the partial nuclear test ban treaty which is specifically about nuclear weapons.
It would be undoubtedly nuclear - and undoubtedly capable of mass destruction - but is it a weapon if the intent is to drop it on the poles of Mars for terraforming - or to deflect an asteroid?
I think we would need an expert on space law to step in here to clarify that one - or if anyone knows of an article on this by an expert on space law?...
In any case if it was needed to deflect an asteroid (very unlikely low probability thing despite the movies as there are much gentler ways to deflect asteroids given more time) - I'm sure that one way or another would be found to make it legally acceptable, some kind of temporary waiver or something as everyone would be agreed on.
And if everyone agreed internationally on the benefits from an attempt to terraform Mars, surely the same.
But you'd need to make sure that everyone understood the intent :).
INTERFERING IN ACTIVITIES OF OTHER PARTIES
Then - the main other thing in the OST is whether you are interfering in the activities of other parties to the treaty. If you drop a nuke on the poles, and someone else in the treaty wants to study some geological formation at the poles, or to study life forms that only exist there if we find such (there's a possibility of seasonal small amounts of liquid water for instance in Richardson crater through the solid state greenhouse effect) that would surely count as interfering with their investigation. Same also if you do it to warm up the planet, and there isn't international agreement to warm the planet.
The relevant article here is - the bits to do with interfering with other parties to the treaty in bold:
Article IX
"In the exploration and use of outer space, including the Moon and other celestial bodies, States Parties to the Treaty shall be guided by the principle of co-operation and mutual assistance and shall conduct all their activities in outer space, including the Moon and other celestial bodies, with due regard to the corresponding interests of all other States Parties to the Treaty. States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of the Earth resulting from the introduction of extraterrestrial matter and, where necessary, shall adopt appropriate measures for this purpose. If a State Party to the Treaty has reason to believe that an activity or experiment planned by it or its nationals in outer space, including the Moon and other celestial bodies, would cause potentially harmful interference with activities of other States Parties in the peaceful exploration and use of outer space, including the Moon and other celestial bodies, it shall undertake appropriate international consultations before proceeding with any such activity or experiment. A State Party to the Treaty which has reason to believe that an activity or experiment planned by another State Party in outer space, including the Moon and other celestial bodies, would cause potentially harmful interference with activities in the peaceful exploration and use of outer space, including the Moon and other celestial bodies, may request consultation concerning the activity or experiment."
This has lead to a huge amount of discussion by lawyers about what this article means, which no way am I the right person to try to explain - but in particular, "harmful contamination" has been taken to include contamination that interferes with the scientific investigations of other parties to the treaty (though not limited to it).
But your settlers anyway would need international agreement there also, on whether or not settling Mars interferes or helps with scientific investigation of the planet.
ANYWAY NUKES CAN'T TERRAFORM MARS
But anyway - nukes won't do the trick. It was just a half joking "off the cuff" remark. There were many news stories that tried to develop it into a fully worked out plan to terraform Mars. But all he says in the interview, in a joking context and tone of voice, is "The fast way is to drop thermonuclear weapons on the poles". That's not a plan. When he has a plan he unveils it in full detail as for hyperloop.
There is no published paper either to back up that idea, at least I can't find one and none of the stories about it mention one. It's just an off the cuff remark in conversation.
NUKES TOO PUNY COMPARED WITH COMETS WHICH HIT MARS ANYWAY
If you look into it some more, it is clear that nukes are nowhere near powerful enough to change the climate of Mars. I worked out that the Tsar Bomba, largest nuke ever built, would be nowhere near as powerful as comet impacts, which happen naturally. You'd need 625,000 Tsar Bombas to equal one comet impact. And they are nowhere near enough to jolt Mars into a new climate equilibrium as they haven't done it yet.
You can also do it another way. By working out the energy needed just to melt ice (ignoring need to raise it to melting point first) and if all the energy from the blast went into melting water, you'd melt enough for a 4.3 micron layer over the surface of Mars with each Tsar Bomba explosion. But of course it wouldn't all go into melting, only a tiny fraction, and the water once melted would freeze over quickly and not much get into the atmosphere. And as for dry ice, it could only liberate 0005% of the current Mars atmosphere - and to tip it into a new greenhouse state, it has to liberate enough for ten times the Mars atmosphere. So, in total - it is just many orders of magnitude too puny to change the Mars atmosphere. Even if that much CO2 existed on Mars, which isn't certain (only a tenth of it found so far) there just isn't enough energy to liberate it unless you can drop many millions, and given that this is a big over estimate of its effect, more likely many billions, of Tsar Bombas on Mars.
Some water vapour and CO2 would be liberated but it would soon condense back to the poles, even if you let off thousands of Tsar Bombas on Mars.
For details, see Why Nukes Can't Terraform Mars - Pack Less Punch Than A Comet Collision
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
4.8m answer views110.3k this month
Top Writer2017, 2016, and 2015
Published WriterHuffPost, Slate, and 4 moreHuffPost, Slate, Forbes, Newsweek, Business Insider, and Science 2.0