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Possibility of igniting Jupiter

  1. Mar 13, 2006 #1
    Now I know the chance that self ignition of Jupiter has less chances than a snowball has to survive in hell. Have there been however serious studies towards the possibility or impossibility of triggering ignition? If the density (Lawson's criterion) and chemical composition (not too many heavier elements) are right, maybe a certain layer could be ignited? Just out of interest.
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  3. Mar 13, 2006 #2


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    A planet is not like a dry forest, waiting for a spark to cause a forest fire. Celestial objects ignite (become a star) when the pressures are high enough for fusion.

    If we could just toss a match on Jupiter, it would already be burning. Comet Shomaker-Levy 9 would have done the trick in 1994 (as well as millions or even billions of other things that have slammed into Jupiter over its lifetime).
  4. Mar 13, 2006 #3


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    Stars don't "burn" via chemical combustion, they sustain nuclear fusion with high temperatures and pressures.

    Jupiter has about 1% of the mass it would need to support nuclear fusion.

    - Warren
  5. Mar 13, 2006 #4


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    I think that would require a very dramatic event -- the conditions inside of Jupiter aren't very close to those needed for nuclear fusion. The part of the planet where most of the action takes place (the surface) is far, far too low density. Interestingly, though, the surface of a white dwarf can undergo spontaneous nuclear fusion as a result of accretion from a binary partner. This is the explanation for some kinds of novae.
  6. Mar 13, 2006 #5


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    Mass is too small to sustain a fusion reaction, as others have mentioned.

    Any initiated fusion reaction (via a manmade fusion device) would be quickly quenched.
  7. Mar 29, 2006 #6
    What if you detnated a nuclear weapon in the atmosphere?I heard some stuff about that.
  8. Mar 29, 2006 #7
    Funny that, because when comet Shomaker levy 9 was about to slam into Jupiter, there were rumors going around that the whole planet could explode, so I asked a science teacher at my school whether it was a possibility, and the answer I got was that because of the combustible gases in the atmosphere it was a possibility. Hmmm, it amazes me how people can ignore simple facts, in this case that there have been millions of past impacts.
  9. Mar 30, 2006 #8


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    Your observation was well reasoned, Vast. Jupiter would have long ago ignited were it remotely capable of sustaining a fusion reaction. The combustible gasses thing is a non-starter. Combustion is a conventional chemical reaction which requires an oxidizer [e.g., oxygen]. A comet composed of pure oxygen would make for some fireworks, but, they would be short lived. The oxygen would be expended in short order. As Einstein observed, physics works pretty much the same everywhere in the universe.
  10. Apr 2, 2006 #9
    what about titan? I heard that if there was just a little free oxygen in Titans atmosphere, it would be possible to light its Natural Gas seas with a single match
  11. Apr 2, 2006 #10


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    1] Planets with atmospheres have meteor showers, and often have lightning. If anything were going to ignite, it would have by now.

    2] We have free oxygen here on Earth, and we have combustible materials (or at least oxidizable materials) such as, oh say, iron. What do we get? We get iron oxide. Chemical reactions don't wait for some catclysmic event, they happen over time. If anyting were gonig to oxidize, it already has.
  12. Apr 3, 2006 #11


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    Ditto for the plunge of the Galileo Spacecraft into Jupiter even more recently.
  13. Apr 3, 2006 #12


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    You wouldn't even see it from Earth. Each of the SL-9 comet fragments unleashed an explosion larger than all the nuclear weapons on Earth combined. And Jupiter is still Jupiter.
  14. Apr 14, 2006 #13
    No, its impossible for a natural cause to ignite a jupier size ball of gas. Yet you could turn other things "on". I was reading the book- Entering Space- and it made a valuable point.
    Jupiter you must first kno,w releases energy that it first got from when it was forming. Any object bigger then Jupiter would have energy that would simply remane with it for nearly ever. Yet heres the light switch part.
    If Humans had enough money we could simply build giant mirrors about .001 microns thick, and place them over key jupiter hot spots. These mirrors force the energy coming from jupiter back onto Jupiter, while taking sunlight and moving its energy onto Jupiter. Yet this cannot work because of Jupiters Sizes. Yet a brown dwarf size object could do this simply. The only problem is getting a brown dwarf close to another energy source with out them eating eahc other.
  15. Apr 15, 2006 #14

    The combustible seas of titan are mostly methane right? What's the estimated temperature of those seas? If you can't raise the temperature high enough, you aren't going to have the energy to break apart existing bonds. I'm thinking even if you had an arbitrary unit of methane and oxygen to burn, it wouldn't release enough energy to ignite the next unit, and the reaction of would die. Anyone with a chem book should be able to crunch the numbers and check this.
  16. Apr 17, 2006 #15


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    Like people have said before you need oxygen to make things burn. If you have a little oxygen on the surface of titan the whole thing isn't going to go up in flames because what little oxygen there is will be used up and the flames quenched. Its like trying to burn awhole lump of coal in a bell jar without adding any new air. Its impossible.
  17. Apr 27, 2006 #16
    Why do we say "burn"? You can't get a planetery mass to burn unless is hass more then 50 %of its mass as oxygen.
  18. Apr 28, 2006 #17


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    Hi Arian! Welcome to PF. What is your point?
  19. Apr 28, 2006 #18


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    Well there are those of us who use burn generically in the sense of producing thermal energy - even nuclear in the case of fission or fusion - and no oxidation is involved. In fact, one measure of energy production in nuclear fuel is burnup, expressed in energy/unit mass (e.g. GWd/tU, or MWd/kgHM, or fima).

    I answered scott1's question previously - a fusion device would not ignite Jupiter's atmosphere - any fusion reaction would be quickly quenched. The electrons from C, N and O quickly dissipate thermal energy by brehmsstrahlung radiation.

    The SL comet was mostly ice, so not free oxygen to burn hydrogen, methane or ammonia in Jupiter's atomsphere.

    As for oxidation in a generic sense, in addition to oxygen, one could use chlorine or fluorine as the oxidizer.

    True, energy-wise, but not temperature wise. Frictional heating of the comet plunging through the atmosphere would generate heat like the Space Shuttle experiences falling through earth's atmosphere - but at higher temperatures ( I need to find a realiable number).

    One estimate of the temperature generated by SL in Jupiter's atmosphere is 50,000 K (90000°F) -
    and http://www.seds.org/sl9/Educator/section07.html [Broken]
    but I think that's too high.

    Incandescent means something like 3000 K (which the space shuttle experiences)

    Still even 50,000 K is less than 5 keV, and sustainable fusion would require temperatures more like 400 keV for p-p fusion. The sun has a temperature about 1290 keV or 15 million K.

    Jupiter's atmosphere - http://zebu.uoregon.edu/ph121/l15.html [Broken]

    http://spaceprojects.arc.nasa.gov/Space_Projects/galileo_probe/htmls/ASI_results.html [Broken]
    Last edited by a moderator: May 2, 2017
  20. May 17, 2006 #19
    Doesn't the Sun's corana have a higher temperature then the surface(maybe the core I'am not sure which)?
  21. Jun 19, 2006 #20
    Sounds like fun, wana make it burn? Send it into the sun, just for the fun of it.
  22. Jun 19, 2006 #21
    Sending jupiter to the sun? That's a new idea to iginte it.
  23. Apr 29, 2010 #22
    i have some questions before i dispute the fact of a possible ignition of jupiter.

    1) jupiter is 90% gas? is this a known fact or is this the case of scientific speculation based on measuring methods?
    cus over recent years i have seen a lot of these peoples so called guestimates proved to be wrong!

    2) what is the pressure level at the centre of jupiters core? does anybody on earth know this?

    3) The great red spot is a storm front right? could somebody please explain to me how a storm can rage with no solid ground bellow it?

    4) infact does anybody know for sure what is bellow jupiters gaseous layers?

    nuclear fusion, we as humans are barely scratching the surface, to think we know it all about nuclear fusion cus we can make a tiny little bomb in comparison to a star or any other heavenly body is just ridiculous.

    i know im boxing outside the so called acceptable known parameters of physic's but we barely know anything about red dwarfs and the size of these objects and how they came to be is still in theoretical stages, so i wouldn't quite yet dispute the fact that jupiter can not ignite
  24. Apr 29, 2010 #23


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    To be sure I understand: You'll discuss exclusively "known facts" about Jupiter, but will not consider anything that is derived from measurements?
  25. Apr 29, 2010 #24
    on the contrary theory is a great part of science to be but theory has to be based on some solid factual information, the topic is very much debatable as we do not know enough about jupiter or saturn to make a claim that it can not or will not ignite one day...the relative information suggest's it will not but there is still yet unexplained energy readings from both these gas giants. most of the data collected on jupiter and saturn is not conclusive infact if i remember rightly there was a lot of errors made while testing theory on these gas giants...we simply don't have enough knowledge on this topic to state it will or won't ignite, and our knowledge base in nuclear physics is some what limited to our experiences...

    im open to listen to any theory factual or not but it doesn't mean i would support the conclusion... here is a web page disclosing certain information on these bodies http://www.astrophysicsspectator.com/topics/planets/GiantGaseousPlanets.html , i tend to favour that our estimates on the size of a gas giant to ignite is floored... there is a direct relation between jupiter and brown dwarfs, both saturn and jupiter are made up of the same material as the sun. what im trying to say here is we might be pleasantly surprised one day, there is something happening at both these gas giants cores that is producing energy and we don't understand it!

    we may find that jupiter is the missing link binding planets to red dwarfs and stars, it is fact though if jupiter did ignite that it wouldn't sustain fusion for a long period of time. maybe 50 years or so (a blink of an eye in relation to stars life span)
  26. Apr 29, 2010 #25
    Jupiter is almost entirely hydrogen-1 and helium-4. Fusion reactions would mainly be proton-proton...and even in the core of our sun, those happen rarely, they only keep the sun glowing because of its enormous volume for its surface area. This is not the reaction used in fusion bombs or fusion reactors, because it's just too hard to make it happen. The deuterium and other substances that can participate in easier fusion reactions are extremely dilute in Jupiter.

    To summarize, getting Jupiter to ignite and fuse at any notable rate would probably require adding so much energy that it'd violently explode even without any fusion going on, and then what fusion occurs would very quickly cease as the planet spreads apart and cools. Getting this to occur...well, tossing Jupiter into the core of a supernova-in-progress would do the job, but these conditions generally just do not occur in the universe. You're certainly not going to "set Jupiter off" with something as tiny as a nuke. There might be small amounts of fusion happening during impact events, but it'd be a raindrop in a hurricane compared to the energy of the impact itself.

    A better bet might be to drop a neutron star into it (or drop it onto a neutron star...the disparities in mass and size cause some issues for language)...packing Jupiter down into a dense atmosphere around a stellar-mass object 24 km across will greatly improve conditions for fusion. Transportation of the planet/neutron star are left as an exercise for the reader...
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