I wonder how much Jupiter atmosphere can be penetrated?

[Lukaszenko]

The plasma inside a tokomak is held in place by a magnetic field. Since the gas inside the reactor is ionized, this is easy. The atmosphere of Jupiter, by contrast is not (as far as we know) a plasma at these altitudes/pressures. In addition,such devices usually cannot operate without some leakage

So wait...could work in the sun, then?

As for Jupiter, is there a way to ionize the atmosphere around you? Assuming we're in the future of course, and have access to insane (but possible) amounts of energy.

[lajoswinkler]

Since a tokamak can function while holding multiples of a star's core inside of itself, would it be possible, theoretically, to have something working on the same principle that can hold extreme heat/ pressure (such as Jupiter) on the outside?

What is "multiples of star's core"? Amount of plasma? No, it can't. Tokamak works with measly amounts of matter.

There's a gotcha there though, the pressure's going to increase the boiling point. To passively vent the water vapour, the pressure inside needs to be at least that outside, and while an active pump might work against the pressure gradient I think it could only go so far.

That is true, and it's an interesting problem to solve. It might be done using a heat exchange loop. One coolant, let's say NaK/Hg, is in a main pressure vessel's coolant system. It collects the heat which has crept inside and gives it to an outer coolant system which is water at environmental pressure, shielded from heat.

Water is extremely poorly compressible, so you just need to keep it relatively cool. IIRC, temperature gradient is gentle compared to pressure gradient in Iovian planets.

I think that is scientifically sound, but the engineering part is tricky. What do you think?

[Beowolf]

Okay, now let's design it as a "sample return" mission. I want a piece of Jupiter brought back to orbit from several hundred km deep.

[lajoswinkler]

Okay, now let's design it as a "sample return" mission. I want a piece of Jupiter brought back to orbit from several hundred km deep.

It won't happen.

[Hannu]

Gas composition of Jupiter's atmosphere would be far more scientifically interesting thing than for example photos. Beautiful turbulence we can see in orbital photos have huge size scale (hundreds or thousands of kilometers) and it can not be seen in atmosphere. Therefore it is probably bad idea to evaporate something to gas around the probe.

You can not use magnetic fields. Material in fusion reactor have very low pressure but in Jupiter's atmosphere there are very high pressure. And as somebody said, gas molecules in Jupiter is mostly electrically neutral and do not react to magnetic field same way than plasma. And if we speculate about unrealistic strong magnetic fields, which can ionize dense gas and keep it away, we face the same problem as with evaporation. Our protection measures change significantly things we want to investigate.

[cantab]

It won't happen.

Not any time in the forseeable future, certainly.

You might be able to get down and back up with a balloon, but it then takes 40 km/s to get into low Jupiter orbit.

[Idobox]

About water cooling: You will start with a chunk of very, very cold ice, and although the latent heat of fusion is lower than the latent heat of evaporation, it is still very high. Because ice takes more volume than steam, you will also have a small advantage with steam pressure build up.

But since we're talking about a super expensive mission, there might be better options than water, although I didn't find anything after a quick googling. Maybe some endothermic reactions?

[Pawelk198604]

Why NASA resigned from using Centaur stage i know that it was related to Challenger disaster, but does is really was so risky?

[Bobnova]

OP didn't say it had to send science back. Freed of that constraint I could easily see us getting a probe to at least the liquid hydrogen, probably the metallic for that matter.

It might just be a lump of Tungsten, but it'd make it!

[InfinityArch]

OP didn't say it had to send science back. Freed of that constraint I could easily see us getting a probe to at least the liquid hydrogen, probably the metallic for that matter.

It might just be a lump of Tungsten, but it'd make it!

IIRC the Galileo probe would have gotten pretty deep into the atmosphere before completely melting (down to the supercritical hydrogen), even though it stopped transmitting from overheating long before then.

Edited October 10, 2014 by InfinityArch