Could Jupiter Be Ignited for Fusion?

[Simon666]

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.

 

[tony873004]

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).

 

[chroot]

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

 

[SpaceTiger]

If the density (Lawson's criterion) and chemical composition (not too many heavier elements) are right, maybe a certain layer could be ignited?

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.

 

[Astronuc]

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.

 

[scott1]

What if you detnated a nuclear weapon in the atmosphere?I heard some stuff about that.

 

[Vast]

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).

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.

 

[Chronos]

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.

 

[OSalcido]

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

 

[DaveC426913]

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

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.

 

[Phobos]

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, ...

Ditto for the plunge of the Galileo Spacecraft into Jupiter even more recently.

 

[russ_watters]

What if you detnated a nuclear weapon in the atmosphere?I heard some stuff about that.

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.

 

[Arian]

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 here's 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 without them eating eahc other.

 

[sceeth0]

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

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.

 

[Kurdt]

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.

 

[Arian]

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.

 

[Chronos]

Hi Arian! Welcome to PF. What is your point?

 

[Astronuc]

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.

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.

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.

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) -
http://www.astrosociety.org/education/publications/tnl/27/jupiter2.html
and http://www.seds.org/sl9/Educator/section07.html
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.
http://csep10.phys.utk.edu/astr162/lect/energy/cno-pp.html

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

http://spaceprojects.arc.nasa.gov/Space_Projects/galileo_probe/htmls/ASI_results.html

 

[scott1]

The sun has a temperature about 1290 keV or 15 million k

Doesn't the Sun's corana have a higher temperature then the surface(maybe the core I'am not sure which)?

 

[Balence]

Sounds like fun, wana make it burn? Send it into the sun, just for the fun of it.

 

[scott1]

Sounds like fun, wana make it burn? Send it into the sun, just for the fun of it.

Sending Jupiter to the sun? That's a new idea to iginte it.

 

[semajenyaw]

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 I am 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

 

[Ich]

is this a known fact or is this the case of scientific speculation based on measuring methods?

To be sure I understand: You'll discuss exclusively "known facts" about Jupiter, but will not consider anything that is derived from measurements?

 

[semajenyaw]

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 I am 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)

 

[cjameshuff]

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...

 

[russ_watters]

Welcome to PF. Please note, first impressions are important. You've shown quite a bit of anti-science attitude in a first post on a science forum. Not a good idea to start that way.

i have some questions before i dispute the fact of a possible ignition of jupiter.

Um, ok...sounds like you already have some preconceptions - not a good way to open up the discussion.

1) Jupiter is 90% gas? is this a known fact or is this the case of scientific speculation based on measuring methods?

As said, your constraint makes little sense because measurements are facts. Everything we know is based on measurements. But let me just explain how we know:

Jupiter's diameter and mass can be directly measured. Based on these measurements, the calculated specific gravity of Jupiter is 1.3, which is 1/4 that of Earth and a little less than the density of aluminum and a little more than water. That precludes Jupiter from being made of any but a handful of very light materials. Next, using known gas laws, a pressure and density gradient can be calculated to predict what the mass of a "gas giant" should be - and Jupiter's mass and volume fit very well with those predictions if it is made mostly of hydrogen and helium.

cus over recent years i have seen a lot of these peoples so called guestimates proved to be wrong!

Unlikely, or you're cherry-picking. A useless comment.

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

As said, it can relatively easily be calculated using known gas laws. You can learn the requested facts from the wiki. It's ironic that you've come here with such arrogant ignorance that you haven't even checked the wiki to learn easy to find facts! It's almost like you are against learning because you may accidentally learn something you don't wan to believe!

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?

There is nothing about a storm that implies that ground needs to be below it. Why do you think there needs to be?

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

What does "for sure" mean? We have theories that strongly match evidence. That's all science can provide.

A probe was sent about 140km into Jupiter's atmosphere, measuring an atmospheric pressure of 24 bar. That's as far as we can know for certain. All else is theory.

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.

No. Fusion is fusion. The reaction is the same whether it happens in a bomb or a star. By definition, if the reaction is different, it isn't fusion. You're just arguing based on your own ignorance here.

i know I am 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

No, you're really just arguing based on your own ignorance. You're saying 'I don't know what is known about Jupiter/fusion/etc therefore nothing is known'. That's obviously absurd. Educate yourself. Don't use your own ignorance as a basis for an assumption that scientists are ignorant.

 

[thecow99]

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

Lots of natural gas, no oxygen. Natural gas does not ignite on it's own. Once the "very little oxygen" was consumed the combustion would stop.

 

[Chronos]

A little oxygen on titan would quickly oxidize a little amount of methane under the right conditions - er, what thecow said. Kind of reminds me of tiny black hole fantasies.

 

[akhil999in]

Why is precision targeting of high speed proton beams at protons not possible, to make them fuse? Why cannot light push the protons of the beam as light is probably the easiest force to concentrate and produce? Why is thermal motion the only way to get it done?

We could then have an automobile running on its own thermonuclear generation, and many other things. End to Green House Gases, Global Warming, etc.

Infinite availability of usable energy could make it feasible to synthesis all material needs of mankind. Separate elements from available rocks and synthesise required goods.

Less nedd for environ unfriendly mining techniques.

 

[akhil999in]

Required quantity could be broken off the Sun and pushed towards Earth, supplying concentrated pollution free energy. A precision targetted very high speed satellite tangentially hitting Sun could slice off a small piece.

Concentrators and reflectors could send strong Sunlight beams to selected spots of Earth, to be converted to usable energy. These could be positioned where their bodies survive the temperature, and still collect significant energy.

Solar energy could be concentrated and beamed to Earth from Moon.

Because of infinite source, no need for high efficiency at that stage. Therefore low technology devices could work.

Imagine one million solar concentrators beaming to Earth from space, each about a square kilometer in collection area.

Even beaming into oceans could partly help.

 

[Mikeral]

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.

From what i can see the surface temperature of Titan is ~94K. The energy typically released by a methane combustion is ~882kJ/mol. i have also found the heat capacity of methane to be 35.69kJ/(mol K). The temperature required to sustain combustion is 580℃(853K) therefore if one reaction were to pass its energy to the next in perfect order, i calculate that you need to increase the temperature by 759℃ in order to do this we need 27088kJ/mol of energy. This energy is much larger than the energy released by the combustion, therefore it is safe to believe that a self sustaining combustion of methane on the surface of Titan would be impossible, the energy need to bring the methane to combustion point is far to great to self-sustain.

I used constants applied at 1ATM, although the pressure on Titan is 1.44ATM, in this case i believe that even with a slight pressure difference, the combustion is still not able to sustain itself, but i might be wrong.

To answer the question, the reaction would ignite the next particle, depending on what your initial energy supply is, but the reaction would eventually die out.

 

[qraal]

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.

"Burn" in the fusion sense. A fusion burn is a self-sustaining fusion reaction, which Jupiter can't sustain with its current mass or composition. With deuterium at 1 in 150 abundance (instead of its normal 1 in 6500) a fusion burn could be triggered by a sufficiently energetic triggering input, but deuterium burning rapidly becomes explosive and the planet would probably blow off its outer layers or even disrupt totally. Fortunately concentrated deuterium is hard to come by in our solar system. Inside brown dwarfs above 13 Jupiter masses the core is hot enough for a sustained burn even at the lower concentration, but it's quickly used up in about 50 million years. For comparison hydrogen fusion in the lowest mass stars can last 10 trillion years.