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So, in one science fiction story, that tries to be as realistic as possible apart from a few space magics, humanity has a contingency plan to blow up Jupiter. As in, totally destroy it in one massive nuclear explosion.

I'd like to know the effects of such an event. Would it totally wreck the Solar System or would the whole thing be a non-issue?

Kyle Oman
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Mandemon
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Note: Lumo's answer went up as I was writing this. His addresses what would happen if you turned Jupiter into a gigantic thermonuclear bomb. This is actually overkill. You only need to provide the gravitational binding energy of Jupiter (it's crazy to say "only" in this context, but nevertheless it is a six order of magnitude difference). This is the scenario that my answer addresses.

Blowing up the Earth is hard, and blowing up Jupiter would be roughly 10000 times as hard. If you don't get everything up to escape velocity eventually some or all of the planet will recoalesce. The explosion needs to provide at least the gravitational binding energy (simplifying that the density is constant throughout the planet):

$$ E = - \frac{3 G M^2}{5r}, $$

which for Jupiter is of the order of $5\times10^{26}$ tons of TNT.

Supposing you manage this the remains of Jupiter will expand in all directions in an incandescent plasma fireball. This wind will scour the surface the Jupiter's moons but otherwise spread rather harmlessly through the solar system. (I'm basing this on the fact that Jupiter's sphere of influence is much smaller than the typical distances between the planets, so the kinetic energy of the debris will be greatly reduced by the time it reaches any other solar system bodies. There is also the inverse square decrease in flux of course. Note: the other answers suggest that there would be enough radiation to heat the Earth appreciably. To really answer this properly you need some idea about how the explosion is going to work. I'm assuming a fairly "efficient" device which puts most of the energy into simply lifting the material out of Jupiter's gravity well.) The surviving moons of Jupiter would fly off into the solar system and orbit the sun in roughly the orbit of Jupiter.

None of the planets would be greatly affected in their orbit, however Jupiter has a long term affect on the orbits of planets and asteroids by exerting periodic gravitational "tugs." These interactions would stop, but it's hard to say what the long term impact of that would be without running simulations. But nothing is going to go flying off in a dramatic way - it would take a very long time for this effect to build up over many orbits.

Michael
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  • There is a 'Universe Sandbox' simulator on steam at the moment, where you can blow up planets and see how it affects things. Will be interesting to try this and see the effects on the rest of the solar system –  Mar 27 '13 at 11:50
  • @RhysW: Universe Sandbox - great for playing around, not known for its accuracy. These tiny orbital perturbations would probably be below its numerical error level unless you run at its highest accuracy settings (4th order Runge-Kutta with a very short time step). Anyway, worth a try. – Michael Mar 27 '13 at 12:36
  • Oh yes definately not overly accurate, but if the effects are big enough it would be noticeable –  Mar 27 '13 at 14:00
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    I think the real problem with this is the mass distribution. You assumed that we use just enough energy to disassociate Jupiter's mass. Then it certainly won't have the energy to escape the sun! And Jupiter's mass is 2.5 times all the other planets combined. Best case scenario Saturn would absorb a large fraction of it, but even if it did Earth would become completely covered in Hydrogen from Jupiter and life would be smothered. Eventually most would boil off, but new planets would form from Jupiter's massive cloud and affect the orbital resonances. – Alan Rominger Mar 27 '13 at 14:48
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    Also, if Jupiter's moons stick around, I doubt their initial orbits will be stable: the four big moons would end up in nearly intersecting eccentric orbits, and would likely start a game of gravitational billiards with each other, and possibly with other bodies in the solar system, until at least some of them got ejected or crashed into something. However, I also suspect that a blast capable of totally dispersing Jupiter might well transfer enough energy to the moons to put them on direct escape trajectories as well; after all, they'd be hit with quite a bit of fast-moving ejecta. – Ilmari Karonen Mar 27 '13 at 14:55
  • Excellent points both of you! – Michael Mar 27 '13 at 15:48
  • @AlanRominger I would think most of the mass of Jupiter would end up in the Sun, ultimately, since if it blows up isotropically the vast majority of it will not end up in the sphere of influence of any planet. Adding Jupiter's mass to the sun would increase the sun's luminosity by around $.3%$, but it's entirely possible we'd escape disaster :) – Chris Feb 01 '18 at 11:42
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The mass of Jupiter is about $10^{27}$ kg which, via $E=mc^2$, translates to $10^{44}$ joules. If one turned the planet into thermonuclear fuel in some way and detonated it immediately, about 1% or $10^{42}$ joules would be released. Because the diameter of Jupiter is about 130,000 km, the blast would last at least half a second or so. So we have $10^{42}$ joules per half a second. It's $2\times 10^{42}$ watts.

The Sun only releases $4\times 10^{26}$ watts of power, so the blast would be $2\times 10^{16}$ times stronger than the Sun. However, looking at the effects on the Earth, we must realize that Jupiter is about 5 times further from the Earth than the Sun, reducing the energy flux by a factor of $5^2=25$. So the half-second blast seems about $10^{15}$ times stronger than the sunshine. The equilibrium temperature is, because of the $\sigma T^4$ law, about $10^4$ times higher than that from the sunshine, about a million degrees.

The Sun warms the Earth by a degree in hours or so. A source that is $10^{15}$ times stronger obviously needs a tiny fraction of a second to reach thousands of degrees and evaporate the matter on the surface. So no doubt about it, the thermonuclear blast of Jupiter would burn and evaporate all nearby sides of all the planets – all of them are comparably far from the ground zero.

On the other hand, would the incoming energy be able to evaporate the whole Earth? We would be getting $10^{15}\times 342\times 4\pi \times 6,378,000^2\sim 2\times 10^{32}$ watts for half a second, about $10^{32}$ joules per the blast and per the surface of the Earth. The specific heats of materials are comparable to $1,000$ joules per Celsius degree and kilogram so we have $10^{29}$ kilogram-degrees to be heated. Divide it by the Earth mass below $10^{25}$ kg to see that you may still heat the material by tens of thousands of degrees by the incoming light. So I do think that this could evaporate the whole Earth but not the largest planets like Saturn.

Needless to say, the Sun itself would be pretty much untouched. Its surface already has 6,000 degrees or so. The strong radiation from Jupiter could bring it to a million of degrees, by the calculation above, but it's the same as the temperature of the interior layers. So the Sun would get destabilized a bit but it would quickly converge back to the Sun we know, I guess.

The calculations above are completely unrealistic because at most, one could think about turning Jupiter into a small star that would still burn very slowly and would be far weaker than the Sun.

Luboš Motl
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    I didn't interpret the question to mean that all of Jupiter is involved in a thermonuclear reaction, only that enough is to unbind the planet. So I've gone with a "minimal" scenario in my answer where all of the energy goes into unbinding Jupiter, with little left over for dangerous radiation. This a comparatively "safe" method, thought I must confess ignorance about which scenario is more plausible. :) – Michael Mar 27 '13 at 10:31
  • LOL, you may be right. At the end, we will choose a method to blow up Jupiter most creatively. ;) – Luboš Motl Mar 27 '13 at 10:42
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    I'll accept this, though Brown's answer is good too :) Different versions is a good thing, since there is not a clear whenever or not the entire Jupiter is used or just parts of it. – Mandemon Mar 27 '13 at 11:58
  • re your last paragraph, 2010? – Tobias Kienzler Mar 27 '13 at 12:14
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    What if Earth and Jupiter were in opposite points in their orbits? Would the two extra AU have an appreciable difference? – Mr.Mindor Mar 27 '13 at 14:34
  • Good calculations. Inspired, I carried out a slightly different method with your numbers: $ 10^{42} J / ( 4 \pi (5 \text{AU})^2 (2260 kJ/kg) (1 g/cm^3) )$. This is the calculation to find the depth of water vaporized by the energy released, divided by the area it's dispersed. After you divide energy by area (J/m^2), then you divide that by the density of water and the heat of boiling of water. This gives me $63,000 km$. So if Earth was all water (at sea level pressure... I know) it would be vaporized. Earth diameter is $12,000 km$, so it seems unsettled. – Alan Rominger Mar 27 '13 at 14:40
  • I disagree with the effects of the blast--it's all coming in very fast, the energy is going to be dumped in the surface layers which will turn to plasma and stop it from penetrating any deeper. Most of that energy is going to be dumped back into space, not go into the planet. The surface will be singed, half the atmosphere will be gone and the blast wave will kill anyone not adequately protected on the other side. I would expect survivors, though. – Loren Pechtel Mar 27 '13 at 17:52
  • @Mr.Mindor increasing the distance from 4.2 to 6.2 AU would reduce the amount of energy received by the Earth by a little more than half from the worst case. However Luboš used 5AU (approx mean distance) for his calculations so the Earth would still take 2/3rds as much even in the best case. A related question that I'm not sure of the answer to would be if - assuming the Earth, the Sun, and Jupiter were perfectly aligned - could the Sun itself effectively shield us from the blast; or would enough energy still be diffracted through its atmosphere to fry us. – Dan Is Fiddling By Firelight Mar 27 '13 at 18:26
  • @DanNeely I saw a figure that the energy required to disassociate its matter is $10^6$ times less than the thermonuclear energy, so it follows that the particles will be traveling very fast. They will be gravitationally deflected by the sun, but if I use the $10^{42} J$ number, I can find that a Hydrogen atom would leave with about 5 MeV of energy. The escape velocity from the sun's surface is only about 1 keV for that particle. I believe this means that the orbital eccentricity is $\gg 1$, so the deflection angle will be small and Earth is safe in the sun's umbra... if we were so lucky... – Alan Rominger Mar 27 '13 at 19:07
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Let's pluck several parameters from Wiki for blowing up the Jupiter. If we compare Earth with Jupiter in terms of mass and volume, it brings us a lot of wonderful numbers.

Volume: $1.4313×10^{15}\text{km}^3$ which can hold $1321$ Earths

Mass: $1.8986×10^{27} \text{kg}$ which is $318\ M_{Earth}$

It's indeed Sci-Fi. Because, simply using the mass-energy equivalence, we can see that it releases about $10^{45}J$, which is a lot of energy, indeed. First, the light along with the gamma rays from the nuclear explosion can easily cross 4 AU distance in about 36 mins to reach Earth. If we're planning to detonate the Jupiter's core, then we're gonna spread out its highly dense $H_2$ and $CH_3$ atmosphere, which can provide a medium for the shock-waves. Then, the highly radioactive radiations are gonna make their way to Earth within several weeks maybe. There will be a lot of consequences for this explosion like,

1) At the time light & gamma rays speed into Earth's atmosphere, we lose all our infrastructure on communications. Satellites in every orbit will be melted.

2) Next, we'll be watching jupiter on fire while we'd be slowly eroded (1 or 2 seconds, maybe) by the highly intense $\gamma$-rays, particles like neutrons and other EM radiation.

3) And, the most important thing. As I've said, the shockwaves would make their path through the spread-out atmosphere, taking the asteroid belt and some broken moons along with it.

Definitely, we won't be here to enjoy the fireworks ;-)

Waffle's Crazy Peanut
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