Fusion of Jupiter

[leax256]

I was reading a thread in suggestions about adding explosives,http://forum.kerbalspaceprogram.com/showthread.php/47807-Explosives-%28Hear-Me-Out%29, it got a bit of topic but made me wonder if it is possible to create a fusion reaction in Jupiter.

what would be required to do such a thing?

begin

edit: I am refering to the possibility for using fusion or fission bombs to start the reaction.

Edited August 27, 2013 by leax256

[Sean Mirrsen]

Clone it about 20 times and pile them together. It might have just enough mass for a brown dwarf.

[leax256]

Clone it about 20 times and pile them together. It might have just enough mass for a brown dwarf.

perhaps I should clarify, reread the top

[LaydeeDem]

No amount of explosion could cause fusion in Jupiter. Jupiter is big, but it simply isn't big enough for fusion. You should read this: http://skeptoid.com/episodes/4143

[TheSaint]

Clone it about 20 times and pile them together. It might have just enough mass for a brown dwarf.

This is correct. In order to sustain fusion in a star you have to have enough pressure to keep the reaction together. Nuclear fusion requires your fuel to be at a very high temperature and pressure in order to overcome the natural electromagnetic repulsion of the atomic nuclei. Nuclear weapons do this by placing the fusion fuel close to a fission bomb, which provides the necessary heat and pressure to instigate the fusion reaction. But a fusion reaction releases immense amounts of energy. The effect of that energy release is to tear the nuclear fuel apart, rendering it unable to continue with a fusion reaction. That is why a very small percentage of the fuel in a nuclear weapon is actually fused, and the rest is released unused.

In the heart of a star, this tendency to disperse the fuel is overcome by the force of gravity. Even with the huge energy release, the fuel is kept in a temperature/pressure configuration that supports ongoing fusion, so the reaction is self sustaining.

So in your Jupiter scenario, your bomb drops to the core of Jupiter and detonates. It fuses its own fuel, it might get some boost by fusing some of the local hydrogen and/or helium, but there is not enough gravity to keep the fuel together, so the energy of the explosion is going to disperse the fuel from the locality of the explosion and the reaction will cease. There will be no sustained fusion reaction.

[leax256]

So in your Jupiter scenario, your bomb drops to the core of Jupiter and detonates. It fuses its own fuel, it might get some boost by fusing some of the local hydrogen and/or helium, but there is not enough gravity to keep the fuel together, so the energy of the explosion is going to disperse the fuel from the locality of the explosion and the reaction will cease. There will be no sustained fusion reaction.

I never specifically said it was to be in the core, the gravity in the core is balanced. I meant higher up

[Sean Mirrsen]

You'd just blow a hole in the atmosphere with a single bomb. But even with thousands/millions/billions of bombs, equally spaced and detonated simultaneously to create the pressure necessary incite fusion inside Jupiter, that fusion would only be sustained for a brief moment - at which point the energy release from the fusion would tear Jupiter (and several neighboring planets) apart.

[lajoswinkler]

So, the answer is no.

[TheSaint]

I never specifically said it was to be in the core, the gravity in the core is balanced. I meant higher up

This statement doesn't make a whole lot of sense. The core is where the pressure and temperature would be the highest. If there isn't enough pressure and temperature there to support fusion, there will be even less as your altitude increases.

[Diche Bach]

600 times bigger than the world's entire nuclear arsenal . . . was a bit skeptical of the basis for such an estimate but sounds like our trusty space probes proved quite useful

.

Instruments on Galileo detected a fireball which reached a peak temperature of about 24,000 K, compared to the typical Jovian cloudtop temperature of about 130 K, before expanding and cooling rapidly to about 1500 K after 40 s. The plume from the fireball quickly reached a height of over 3,000 km.[14] A few minutes after the impact fireball was detected, Galileo measured renewed heating, probably due to ejected material falling back onto the planet. Earth-based observers detected the fireball rising over the limb of the planet shortly after the initial impact.[15]

I've expressed confidence that humanity could not be driven into extinction by any cosmic event short of the sun's final death throes in a billion years, but having read this I'm actually beginning to wonder.

What the heck would a comet that big do to Earth? Was the size of that detonation something to do with a comet entering a largely hydrogen atmosophere? Or would it be just as explosive if it intersected Earth?

[ravener]

This statement doesn't make a whole lot of sense. The core is where the pressure and temperature would be the highest. If there isn't enough pressure and temperature there to support fusion, there will be even less as your altitude increases.

we make hydrogen bombs on earth, if we could get the same reaction, just with the atmosphere as the fusable material the chain reaction would probbably reach further than any closed bomb could... if we just could get the reaction started... tsar bomb anyone?

we arent talking about sustained fusion guys, we are talking about a bright flash and a yellow jupiter (until it cools down).

disclaimer: i am in no way a nuclear scientist, just say'n.

[SargeRho]

Hydrogen bombs have never reached ignition. And probably won't.

[leax256]

Hydrogen bombs have never reached ignition. And probably won't.

how much fusionable material would it take?

[Sean Mirrsen]

we make hydrogen bombs on earth, if we could get the same reaction, just with the atmosphere as the fusable material the chain reaction would probbably reach further than any closed bomb could... if we just could get the reaction started... tsar bomb anyone?

we arent talking about sustained fusion guys, we are talking about a bright flash and a yellow jupiter (until it cools down).

disclaimer: i am in no way a nuclear scientist, just say'n.

You do realize why a hydrogen bomb is called a bomb, right? Because it explodes?

Even in a successful freak runaway fusion reaction scenario, you would get a fusion bomb the size of a gas giant. You'd get a bright flash, and a big expanding cloud of superheated yellow Jupiter, because all that energy would have no force - i.e. gravity - to contain it.

[Winter Man]

I quite liked the idea in the Mars trilogy of loads of floating fusion reactors in the high atmosphere of Jupiter, just putting out light for the colonists on the moons.

[SargeRho]

About 20-50 Jupiter masses would be needed for a self-sustaining fusion reaction.

[Moon Goddess]

What the heck would a comet that big do to Earth? Was the size of that detonation something to do with a comet entering a largely hydrogen atmosophere? Or would it be just as explosive if it intersected Earth?

Well I went to this website http://www.purdue.edu/impactearth/ But I couldn't figure out how to run the numbers with multiple impacts.

So I put the comet back together to it's 5km original form and slammed it into earth as it's original speed of 60km/s I also plugged in pure ice, cuz I wasn't sure.

I figured, lets stand 500km from impact and see what happens to us.

Energy

Energy before atmospheric entry: 1.18 x 10^23 Joules = 2.81 x 10^7 MegaTons TNT

The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 6 x 10^7 years

Ouch, thats 28.1 TeraTons of TNT So no, hitting rock instead of cushiony hydrogen made it worse.

Crater

Transient Crater Diameter: 47.9 km ( = 29.8 miles )

Transient Crater Depth: 16.9 km ( = 10.5 miles )

Final Crater Diameter: 79.7 km ( = 49.5 miles )

Final Crater Depth: 1.11 km ( = 0.686 miles )

The crater formed is a complex crater.

The volume of the target melted or vaporized is 903 km^3 ( = 217 miles^3 )

Roughly half the melt remains in the crater, where its average thickness is 501 meters ( = 1640 feet ).

So miles and miles of melted rock, some of it vaporized and hangin in the air as clouds. Not pleasant at all.

At our location 500 km away, first we encounter the heat wave less than 2 seconds after impact

Time for maximum radiation: 1.64 seconds after impact

Visible fireball radius: 78.2 km ( = 48.6 miles )

The fireball appears 35.6 times larger than the sun

Thermal Exposure: 1.67 x 10^8 Joules/m^2

Duration of Irradiation: 21.2 minutes

Radiant flux (relative to the sun): 131

Effects of Thermal Radiation:

Clothing ignites.

Much of the body suffers third degree burns.

Newspaper ignites.

Plywood flames.

Deciduous trees ignite.

Grass ignites.

I think we might be dead... But if we survive, a minute and a half after impact.

The major seismic shaking will arrive approximately 1.67 minutes after impact.

Richter Scale Magnitude: 9.6 (This is greater than any earthquake in recorded history)

Mercalli Scale Intensity at a distance of 500 km:

Damage slight in specially designed structures; considerable damage in ordinary substantial buildings with partial collapse. Damage great in poorly built structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned.

Ok, so some earthquake safe buildings are still standing, if they didn't burn that is.... so like if stay inside we might be ok, lets wait this out.

another 4 minutes later..

The ejecta will arrive approximately 5.57 minutes after the impact.

At your position there is a fine dusting of ejecta with occasional larger fragments.

Average Ejecta Thickness: 37.6 cm ( = 14.8 inches )

Mean Fragment Diameter: 7.52 mm ( = 2.96 tenths of an inch )

Better stay inside.

Ok so it's been 20 minutes now, everything seems to have calmed down the shaking stopped. The fires are starting to go out. Maybe we can go outside now.

The air blast will arrive approximately 25.3 minutes after impact.

Peak Overpressure: 240000 Pa = 2.4 bars = 34 psi

Max wind velocity: 323 m/s = 723 mph

Sound Intensity: 108 dB (May cause ear pain)

Damage Description:

Multistory wall-bearing buildings will collapse.

Wood frame buildings will almost completely collapse.

Highway truss bridges will collapse.

Glass windows will shatter.

Up to 90 percent of trees blown down; remainder stripped of branches and leaves.

Ouch...

If you want some real fun, plug in Comet Hale Bopp estimated size of 60km and speed of 52.5 km/s and see how far away you have to stand to survive.

Edited August 28, 2013 by Moon Goddess

[Diche Bach]

Okay, so 5km diameter, 1000 kg/m^3 density, 45 degree angle, striking 1000m thick sedimentary rock (St. Louis, MO lets say). Distance from impact, 6,700 km (London), which is about halfway around the planet.

In sum, based on my first simulation effects seem negligible that far away, though I cannot get the site to run at the moment to double check if it postulates any climactic effects.

A global winter I think humanity can survive. After all, our ancestors survived the last few ice ages and that was before they had writing, metal, plastics, firearms, etc. A severe global winter could be very, VERY destructive. But even if it kills off 99.9% of humanity, we have been through at least one severe bottleneck event where we were reduced to only about 10,000 individuals (about 200,000 years ago) so there is a precednet for us being able to do it again, especially now that we have advanced technology. Depending on the sort of social order that arose out of that sort of catastrophe, in the long-term it might almost be the best thing for Earth and humanity.

[Moon Goddess]

Yeah but I said Hale Bopp 60km not 5. Even at London it's a equivalent of an 11.7 earthquake... Hale Bopp does cross our obit but chance of impact is very very very low.

What I worry about is something big that we havnt' seen, something couple hundred kilometers across, and not all icy and visible.

Then we get something like this

And I just realized that we've gone very very off topic here, and I apologize.

[Jackissimus]

Yeah but ...

That thing we would almost certainly see. What worries me more are rocks about 100-300m in size, we won't be able to see those in advance.

Here's the same video with commentary:

[Diche Bach]

So okay, a 500km death star (complete with glowing evil traces of volcanic MAAGMAA) comes hurtling out of the cosmos and we're toast. Literally! ToAST! GET it!?

Love the fear mongering the Discovery Channel has resorted to capture people's attention. "It is estimated that impacts of this sort have happened six times during the Earth's violent history" . . . Well sure! During the first couple billion years, referred to as the Late Heavy Bombardment Phase before the messy solar system got swept up and the Earth and other planets were 'still in the oven' and not quite fully baked

This period of heavy bombardment lasted several hundred million years and is evident in the cratering still visible on geologically dead bodies of the inner Solar System such as the Moon and Mercury.[2][61] The oldest known evidence for life on Earth dates to 3.8 billion years agoâ€â€almost immediately after the end of the Late Heavy Bombardment.[62]

Short of a rogue planet hurtling in from interstellar space I cannot imagine how a 50km object, much less a 500km object is a real threat.

If OP is irritated that this is OT just let us know and we'll take it to a new thread. But given the thread's topic is "Fusion of Jupiter" I figure you're probably as open to a bit of wild speculation about big cataclysmic events as any of us

[PakledHostage]

Since we seem to be firmly off topic, I thought I'd add that the most realistic "nightmare scenario" is that we discover something like comet C/2013 A1 Siding Spring on a collision course with Earth.

For a brief period after it was discovered this past January, it was predicted that comet C/2013 A1 could impact Mars at a relative speed of 56 km/second. The comet was only discovered in January because it is an Oort cloud comet that is on its first pass through the inner solar system in recorded history. The current best guess of its size is 4 km diameter, but initial estimates ranged as high as 50 km diameter. The most recent trajectory calculations predict that it will miss Mars, passing between 37000 km and 210000 km from Mars' centre on October 19th, 2014 at 18:41 UT.

In the event that a comet like C/2013 A1 Siding Spring was discovered to be on a collision trajectory with the Earth, we may only have a year or so to prepare.

[leax256]

what have I started?

[Seret]

So okay, a 500km death star (complete with glowing evil traces of volcanic MAAGMAA) comes hurtling out of the cosmos and we're toast. Literally! ToAST! GET it!?

Luckily for us big ol' Jupiter usually steps up and takes the hit. Having a massive gas giant in the neighbourhood certainly makes life easier here on Earth.

[magnemoe]

Luckily for us big ol' Jupiter usually steps up and takes the hit. Having a massive gas giant in the neighbourhood certainly makes life easier here on Earth.

Yes, anything crossing Jupiter's orbit will have problems over time, however 500 km rouges has not been around since the creation of the solar system.

I don't think most hit Jupiter, its usually sent outward on an long trip it might not return from.

Mun in KSP has lot of the same effect, if you drop stuff in an Kerbin to Minmus transfer orbit it will usually end up in solar orbit pretty fast. Much more likely than it impact Kerbin or Mun.