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How can I explain that the Atmosphere will burn?

  1. Jul 8, 2013 #1
    Dear Phyisics Forum,

    I registered here in hope to find some help as I plan a videogame and really have to solve some "small" idea I have. More likely a way how to explain it. In basic I want to explain how a Nuclear Explosion ("regular" Nuke with uranium, i guess) can cause a chain reaction that the whole Air, if not even atmosphere catches fire and burns up.

    And before replies come with the Nitrogen and Oxygen etc. "My Earth" has another scenario... So read on before creating an answer:

    1. The earth is covered in a Virus (micro-biological organism?) AND / OR Gas, not sure yet if it's both or either... But most likely both

    2. The virus (if chosen) has even manipulated plants that they produce no more Oxygen but more poisonous gas / toxin (does that even sound realistic, because that is also one of my basic ideas, also they only live from water and sun)

    3. My idea is that the EXTREME HIGH temperature of the nuclear explosion would cause the virus (organism) and / or the gas to a chain reaction that it would burn the whole planet surface down and / or atmosphere, while everything under the surface (earth and water) stays safe, though the atmosphere would be gone and living as we know it would be impossible.

    4. I look for ANY idea that sounds plausible enough how this could happen, e.g. a gas that only burns in extreme high temperatures (thousands of degrees celsius) or if it sounds logical enough that the virus (organism) would burn all over the earth and since it infested the whole world and covered everything due being in the toxin / gas that is produced by the plants, everything else would burn along too.

    5. If you have other clues which are not based on my scenario, please let me know under which conditions the Atmosphere could be erased (still with the nuclear weapon being the trigger of the event)

    If you need any more information of what I have in mind or you do not understand something of what I formulated here please let me know in a reply in this forum and I will do my best to clear some things up. Also I thank you all for reading and replying in advance!
  2. jcsd
  3. Jul 8, 2013 #2
    I think any ideas we could come up with would be so far removed from reality that your audience would just have to suspend disbelief and accept it (:p).

    If the process you're talking about occurred through ordinary combustion, its activation energy would need to be high enough where lightning strikes and other electrical phenomena did not ignite the atmosphere spontaneously. However, for the process to be self-continuing, each reaction would need to release an amount of energy greater than the activation energy! So you're talking about a gas with ridiculously high amounts of chemical potential energy, where each interaction releases as much localized energy as a lightning bolt. My analysis may be off, but I think that kind of worldwide explosion would destroy the Earth. A reaction which requires a nuclear weapon to set it off would pretty certainly wreck a few things!

    Anyway, it doesn't matter so much for a piece of fiction to be rigorously correct. If your game is fun, I'm sure no one will care.
  4. Jul 8, 2013 #3
    Thanks for the fast reply! And yeah well... I have some kinda same issues regarding the reality...

    to give some facts off:

    That virus got launched all over the world via Rockets which in basic are manipulated by human to make the air unbreathable / whoever breathes it in dies a really painful but still medium fast way. While gas masks and mobile oxygen tanks / breath machines are helping against it as it's a virus which only affects organic beings by breathing in. And this virus is ALL over the world.

    So I was hoping it would sound logic enough that a nuclear weapon (wherever it in the end explodes) would give enough of heat and shockwave to give that virus, which in basic is a micro biological organism that it all gets blazed and just burns all away.

    Besides that I could easily explain why there is no lightning and rain due to the virus as it for example would eat the oxygen in the air or transform it into the same toxin which the plants are producing. Therefore the only really heat source would be only that one Nuclear Weapon.

    And believe me, the game is gonna be fun.... Once it's made (give me around 18 months till development starts as I just started putting it together and work full-time besides making it xD)

    BTW! The virus is not only experimental but nobody on the world really has a clue what it was based on or how strongly mutated it is, therefore I can pretty much explain everything with it, even 42!

    And the virus has / had good 20-30 years to cover the whole earth till the point where the actual game starts.
    Last edited by a moderator: Jul 8, 2013
  5. Jul 8, 2013 #4


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    1. A virus would not "coat" the earth, as viruses are incredibly tiny and require other living cells to replicate. It's just not possible for that much "viral biomass" to accumulate unless. A gas MIGHT work, except that your way of producing it through plants is probably flawed. Also, viruses cannot "eat" the oxygen out of the air. Bacteria could however. Single cell photosynthetic organisms make up a large variety of algae.

    2. Plants take in CO2 and water to make sugars and give up O2 as a waste product. I don't know what kind of gas could be made that includes oxygen in the molecule, but it would require an enormous amount of whatever other substance you need, and you'd have to have some way to provide it to the plants, as they get everything from the air and soil. Also, plants cannot live purely off water and sunlight. They require carbon dioxide from the air, and dozens of other elements from the soil.

    However, if you use a bacteria, you could have it genetically engineered to eat certain substances and give off waste products, which could potentially be this gas you want. I really don't know if there is an existing gas that would work however.

    3. I'm not sure, but there may be plenty of other things that reach a high enough temperature to set off this chain reaction.

    4 & 5. Can't help you there. I can't imagine there being anything that would require a nuke to set off the chain reaction. However, you might get away with saying that the nuke just happened to be the triggering agent. Or perhaps that at the time of detonation the conditions of the atmosphere finally reached the right proportions to support a wide scale chain reaction.
  6. Jul 8, 2013 #5
    First of all thanks for your answer.

    Secondly thanks for your reasonable explaining

    Thirdly my feedback and an idea I just got:

    Since I am still in the basic / concept phase of my game I got on the idea to explain it like in the background story and at the start that it would be a bacteria (getting away from the virus, thanks to you and your explanation). But that it later (during gameplay) is discovered that it were Nanobots which started to engineer the plants and perhaps make them even part machine or that the nanobots actually "feed" them with the required needs and changed them that far till they started to produce a toxin gas.

    Furthermore the Nanobots could also explain why the humans started to die, but for example the plants are still alive, as they were programmed to only kill organic beings with human DNA and only when they enter through mouth or nose into a human body, that way nobody would suspect it being something else than a virus, bacteria or gas (as they only enter through air / breathing into the human body). And to finish the whole deal they could be highly flammable, once their material / metal coat starts to melt. Therefore all the nanobots (which eventually even replicate) could cause the whole atmosphere / air burn by something as enormous as a nuke because they are scattered all over the air anyway due to their size and weight.

    Does this sound more realistic? Also I think this would suit better into the whole plot, since it is more advanced than today's technology and after all it is supposed to play in the near, but still, future. (around 2060-2080)
  7. Jul 10, 2013 #6
    "The atmosphere has a mass of about 5×10(18) kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface." (wiki)

    In order for a gas to burn, it needs to have a certain concentration of oxygen and the combustible gas. The amount of combustible gas varies depending upon the substance - but you're looking at a significant percentage of 5,000,000,000,000,000,000 kg of gas, also known as 5 zettagrams (Zg). Ten to thirty percent of that would probably do the trick... and the gas would have to be of similar density as our atmosphere at sea level.

    Wavehandium. Or black magic. If there were any less complicated way to ignite an atmosphere, it would have happened by now - we've had lightning strikes, meteor impacts, and multiple nuclear detonations without anything resembling this.

    If you have a much, much smaller sealed environment, such as a space station, tunnel, domed city, missile silo, or the like, you might be able to raise the concentration of flammable gas to the point at which it could support combustion - but you're still looking at a volume of gas that's ten to thirty percent as large as the volume of atmosphere you wish to ignite.
  8. Jul 10, 2013 #7
    Also - if you have self replicating nanobots, setting fire to the planet isn't needed - you have grey goo and all life on the planet will die within a fairly short length of time - and eventually the planet will be a planet-sized mass of nanobots, as everything that can be converted into nanobots will be. If they replicate using common materials, they will eat all the matter that they need - the planet will be deader than disco, and if those nanobots ever escape into space (due to meteor impact, or being transported via escaping starships) they'll do the same to whatever other planets they land upon.
  9. Jul 10, 2013 #8
    Well you have to keep in mind we are not talking about nanobots with the programming and advanced technology like Replicators / Asurans from Stargate or the Borg from Star Trek. These Nanobots are more prototype-wise and therefore still may have flaws.

    Though you got a good point, StrayCatalyst and I thank you for that, I probably would have not thought about that, therefore I will make sure to make it still plausible enough how the whole world could not rotten / be consumed by these little metallic omnivores.

    There growth and spreading I can slow down with explaining since they were prototypes that their replication is not that efficient and that millions of the nanobots broke upon launch (distribution system = rocket) and others did not activate and therefore just laying around, doing nothing. Also the growth can be limited by explaining which resources they need to replicate and how they do it in the end. Or even that a glitch in the program caused a few hundred thousand to make them start eating each other as they thought they were the raw material, since the material is the same.

    It all is in near future (around 2040-2060) so the nanobot technology could be still pretty tricky and complicated, especially if in use of war.
  10. Jul 10, 2013 #9
    If one self-assembling nanobot exists, and uses readily available materials - game over, unless there's something to regulate its reproduction. Assuming it takes a thousand seconds to produce one nanobot (arbitrary number, not based on science) then in 1000 seconds, there are two of them. A thousand seconds later, four. Then eight, sixteen, 32, and upwards at a steady power of two.

    Assuming a ready supply of chemicals, in eight hours there are sixty eight billion of them. and a thousand seconds later, that number also doubles.

    I'd recommend against nanotech as wavehandium.
  11. Jul 10, 2013 #10
    Well I most likely decided already on the Nanobots and there can be many reasons as I wrote one post before how to slow down the process to make it not sound too "Uber-Tech", furthermore they could be even programmed that they only exist to a limited amount of time or in a limited amount of numbers, for example to keep them in control and not in the end causing world's doom.

    Imagine they are all communicating with each other via sensors each of them carry in them and therefore connect into one huge network no out-side source can access to, or perhaps can, if they could hack one of the nanobots. And since they are all connected with each other they could count the number of signals which are coming in and out, once a signal disappears, the "disappeared" nanobot will be replaced by a newly produced one. That way it is an automated programmed population controller included.
  12. Aug 27, 2013 #11


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    I don't understand the point of igniting the atmosphere though. If anyone survived the explosion they would be trapped underground forever, only ever able to visit the surface in a suit or sealed vehicle . IF this virus/plague/nanobot/whatever. is not directly attacking humans but simply making it impossible to breath the air...then it seems needlessly pointless to vaporize our atmosphere. just stay underground or go topside in a suit. either way you are hosed. blowing up the air just seems needlessly reckless since it is a "cure the disease by killing the patient" route.

    Besides blowing up the atmosphere never works, a friend of mine tried to do it in a story she is writing and we couldn't find a realistic way to make it happen, and Jupiter is made of hydrogen....that stuff WANTS to ignite :)
  13. Aug 27, 2013 #12
    Nobody replied here for so long, lol! And well some stuff has changed in the meanwhile.

    1st the Nanobots are entering human lungs through nose and / or mouth, destroy it / damage it so far till they collapse.

    2nd Nanobots destroy themselves / decay and leave a bacteria behind to cover their existence

    3rd Humans at this point only can go outside by wearing a full protection mask / hazard suit (like those radiation protection / chemical protection suits) & oxygen tanks (nanobots still enter through gas masks)

    4th The atmosphere has to be destroyed / ignited to destroy the hopes of mankind to restore earth to it's former status, so that other goals have to be found and achieved. Which at this point will be really only colonizing a new planet.

    5th I will go with the nuclear weapon ignites all nanobots which will blow up their carried energy source which starts a chain reaction all over the world and causes flames so much in amount that they use all the remaining oxygen or at least so much that no lifeform can exist any longer outside of underground facilities / bunkers (I Have something else in mind but that way you know what kind of buildings I mean)

    6th do not forget it is in the future pretty much around 2075-90 (at least that's around when that nuclear weapon will be launched) and with more and more of the ozone gone and more extreme climatic changes.... such a thing does not seem too impossible.
  14. Aug 27, 2013 #13


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    Well its a game and games run on action, you have huge artistic licence with reality. However I still maintain the "cure" is very irrational. IF you totally destroy the atmosphere then basically you are looking at the moon. There will be 0 hope of ever recolonizing the planet because you can just break out the O2 tanks and refill the air. the surface would be a baren and deadly place filled with solar radiation. Humans in this future remain cave dwellers.

    a few ideas if you wish:

    1) blowing up the atmosphere was not the original intent, maybe the bomb was just supposed to short the nanobots out, perhaps with an EMP. but the scientists didn't anticipate the nanobots exploding in a chain reaction so in the end you have defeated the enemy but you are left with a planet that is still hostile to life. its just the environment that is your enemy this time instead of nanobots. this leaves for a very dark and bittersweet ending to the game.

    2) maybe you don't need to vaporize the atmosphere, if the nanobots go off in a chain reaction and there is some unforeseen side effect that absorbs all the O2 on the planet, well you would end up with a world that still had an atmosphere, plant life could still grow (once the dust settled) but humans would have some major reconstruction to do before they could walk the surface un protected. In this scenario the humans could walk around with breathing masks because the air is still there and the surface pressure would likely still be within normal limits so they would just need a breather with O2.

    Wiping out the O2 is slightly more feasible then vaporizing the atmosphere because there is A LOT of atmosphere on earth and it would take a cataclysmic amount of energy to remove it all, that energy release would not be friendly to anyone anywhere near the surface and would leave the Earth with a moon like surface.
  15. Aug 27, 2013 #14
    Well I have a bit different ideas / solutions....

    1. Cure of the planet will be only available really when the nuke event is prevented (it's not a forced event during the game, but can pretty much ruin your game if you do not figure it out, lol!)

    2. The solutions I have for the game / possible endings are not all just "restoring earth" 1 of my solutions are even transferring humans into android bodies, bam no more food, oxygen, etc. needed except maintenance.

    3. The Nuclear weapon is / will be intended in-game to get rid of some after-war leftovers known as North America, but because of the nanobots *kabooom*

    4. the EMP will be one solution to actually get rid of the Nanobots (though the earth is still in a crappy condition because of bio-engineered plants which started to produce a toxin gas)

    5. there won't be an "evil enemy", only your decisions, perception and influence of others. So for example american characters will tell you how evil the russians and chinese are, while the russians and chinese will tell you how evil the americans are.

    6. I like your idea with the O2 absorb and then building stuff up again somehow, but I prefer to have a more... doomsday scenario, though I will keep it in the back of my head as I proceed with the project.

    7. Regarding colonizing new worlds, in my scenario mankind found a way how to launch a ready-to-go building into space, including a safe landing (at least in simulations) which completely offers life support with all it comes with.... Except Water but for that there are huge storage rooms, right? Also it should be used for a HABITABLE planet... or something like the Mars where Ice / Water reservoirs are that could be used. After all we are talking here in about 30-40 year of future! and we managed "short" after world war 2 to get people on the moon and even built in the meanwhile a space station, another 30-40 years and space colonization does not look that bad anymore (especially as we are working on extreme efficient engines at the moment)

    Also I kinda plan to get the Earth to become something like Mars, a dead rock which was (probably) sometimes looooooong ago a nice place to live at.
  16. Aug 29, 2013 #15


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    well good luck. give us a shout when the game is ready. if its available on the PC platform I will give it a shot.
  17. Aug 29, 2013 #16
    I plan to release it for PC as main platform, EVENTUALLY PS4 port, X-Box One depends on policies & support, Wii U rather not (lack of userbase, not really indie-friendly, developing there is more difficult). But I will let you know with the solution I came up with in the end (still could scrap the whole idea of atmosphere setting ablaze) and of course once the game is done (because then the topic can be closed :P)
  18. Aug 29, 2013 #17


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    As to setting the air ablaze, what if the by product of these nanobots is the fuel for the blaze? If there are billions or trillions of these things floating in the air, what if the key to defeating them was hacking into one, firewalls in the programming might not let them be destroyed outright but what if the players could hack them to start producing methane as a byproduct? with trillions of them rapidly spewing out methane it wouldn't be long before the air was saturated, then light the nuke (or really any good spark. even a lightning bolt would do) and WOOOOOSH. there is your blaze.
  19. Aug 29, 2013 #18
    I like the idea.... so what if they produce as a by-product, without the hack just through the way they are constructed, Methane? And the Toxin gas that the plants started to produce has also a very small amount of methane in the air-mix. This way there would be enough methane over the decades.... and with the additional boom from the nanobots and their batteries / generators it would give enough boost to accomplish that whole thing actually.

    Because the thing is... the player wants to... or should (I won't force the player to) want to save the world, so hacking into the nanobots to force them to produce Methane would be anti-productive. Though perhaps the nanobots malfunctioned sometimes during the time and for example they were affected by some kind of small data loss that included filters or something that should prevent something like Methane production / spread.

    Though things like that kept me rather off because as you said any spark would pretty much cause that, lol, probably even when somebody plays with a flamethrower or turns a car on or makes a bonfire in the wildness!

    I will think about it, perhaps I can create a plot or a combo that will allow this to work out. E.G. that somebody just a day or few hours before the nuke is fired hacked into the nanobots in attempt to deactivate them, but only was able to disable a few side-functions (including the methane filter) and therefore the methane couldn't spread enough that a small spark would ignite everything till the point of the nuke. After all the nanobots won't produce that much methane I assume and rather have it just inside in their iron heart and through the nuke it has enough heat and range to cause a chain reaction that causes the nanobots to explode and through the methane production it will be like the whole earth went on fire. Till of course all the oxygen is wasted / atmosphere too weakened and all the fire goes out due to no more oxygen to flame ;)

    ps: I wrote as I thought so you can follow my thoughts.... but the last paragraph will be most likely what I will come up with, but thank you a lot! please write me to andreas.krewer@gmx.net a personal e-mail so that I won't forget you to mention in the credits or for eventual future science questions ;)
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