I wonder how much Jupiter atmosphere can be penetrated?

[Pawelk198604]

I mean to send probe into Jupiter atmosphere i known it's impossible to reach jupiter core, i known that NASA did once such mission.

[SargeRho]

Depends on your probe's material. The Galileo Probe stopped transmitting 156 km into Jupiter's atmosphere, where the pressure reached 23 atmospheres.

[magnemoe]

Well you face three problems, one is pressure. the other is heat and last you might want to send data back.

Increasing pressure resistance increases weight, same does heat shielding and management.

[cantab]

Well 92 atm is survivable, we know that from Venus landings. I suspect the main issue is how deep can the probe go and still have the atmosphere above it be radiotransparent.

[Lukaszenko]

We know 1000 atm is survivable, from Mariana Trench landings

But yeah, all the other issues...

[Idobox]

Well 92 atm is survivable, we know that from Venus landings. I suspect the main issue is how deep can the probe go and still have the atmosphere above it be radiotransparent.

The atmosphere of Jupiter is mostly hydrogen, if you choose your frequency right, it will stay radiotransparent until you start to get metallic hydrogen. At around 250 000 atm.

Pressure and temperature will be major issues long before atmosphere transparency begins to even be noticeable

[Motokid600]

The heat would melt any transmitter after so long. The probe would have to be a think walled sphere of very durable and high temp metal. But even if you can have the components inside survive... How can any external transmission/camera components survive? Because... That would be the greatest picture beyond imagination.

[cantab]

If the probe body was two hemispheres with an insulator (maybe a strong ceramic) between them, then it could be used as the antenna itself. The toughest instruments would have to work by measuring conditions inside the probe body.

[CavemanNinja]

The picture would probably be flat black, simply because of the probe's depth within the atmosphere.

Of course, this is disregarding a melted camera lens screwing with things.

[cantab]

Indeed eventually it would go dark. That would be part of the results, since it would give information about the atmosphere's opacity with depth.

[Linear]

Indeed eventually it would go dark. That would be part of the results, since it would give information about the atmosphere's opacity with depth.

Spoken like a proper physicist. Being wrong or getting results you didn't expect is awesome.

[Motokid600]

The pictures up until that depth.. is what id want to see.

[-Velocity-]

Indeed eventually it would go dark. That would be part of the results, since it would give information about the atmosphere's opacity with depth.

Yea, at some point it would have to go dark, since Jupiter does not glow in the visible spectrum, so we know that light cannot penetrate to (or escape from) the depths where Jupiter is hot enough to glow in the visible spectrum. But eventually, it would get bright again... VERY bright.

[GreeningGalaxy]

Would it make any sense to have a tiny openable viewport with a tough metal shield over it for a camera? You could just pop it open for a split second to take a picture and check the light level before closing it again. Eventually even that little exposure would break the camera, of course, but it might cut down on cumulative exposure effects as you dropped deeper and deeper.

Is having something that works as a good shield but can also open and close for a camera very quickly even feasible?

[Dkmdlb]

It would be easier just to have a small window through which the camera took photos.

[GreeningGalaxy]

Well yes, you'd definitely have a window and not just stick the camera out in the open. The trouble is, though, I don't think there are very many transparent-enough materials that can match the heat tolerance of the best heat-resistant metal. That's why I think the shielded-shutter idea might help a little bit, to protect the transparent window and the instruments behind it while not in use. You could probably further improve the window's survivability by making it very small and surrounding it with active cooling tubes, but a shielded shutter would probably help a lot too.

[cantab]

Fused quartz is pretty resilient. As in, it can be used to hold molten steel resilient.

Indeed a metal shell might not be a good idea anyway because while strong and with a high melting point it's going to conduct the heat straight into the interior. If the probe is heat-limited then a much more insulating material such as some sort of ceramic may be better.

Of course fused quartz isn't going to match the likes of tantalum hafnium carbide, or even tungsten metal, but it can go impressively deep into Jupiter nonetheless.

Edited October 1, 2014 by cantab

[-Velocity-]

Fused quartz is pretty resilient. As in, it can be used to hold molten steel resilient.

Indeed a metal shell might not be a good idea anyway because while strong and with a high melting point it's going to conduct the heat straight into the interior. If the probe is heat-limited then a much more insulating material such as some sort of ceramic may be better.

Of course fused quartz isn't going to match the likes of tantalum hafnium carbide, or even tungsten metal, but it can go impressively deep into Jupiter nonetheless.

Fused quartz/silica only goes up to like 1500 C.

For taking pictures, perhaps you could use a pinhole camera that's uncovered and recovered very quickly? But with any picture taking system, you're rapidly going to lose resolution due to refraction effects caused by thermal and pressure gradients. It would be like trying to take a picture of something through the air above a hot grill, only 100X worse.

Anyway, it's silly anyway, I'm pretty sure humanity will never be able to go deep enough into Jupiter to take pictures where it's hot enough for the air itself to glow, and even if it were possible, how would the images get returned? The only way I could imagine we could ever achieve something like this would be if a special field of very high temperature electronics were to develop- electronics that functioned at 1000 C or more. We are actually slowly developing such electronics but the field is in its infancy. There is only a small demand too- and small demand means SLOW development rate. Maybe, 1000 years from now....

[lajoswinkler]

The probe could have windows made out of aluminium oxide. Synthetic corundum (or sapphire, if you're more familiar with that name) optical windows allow for UV, VIS and IR transparency.

It's pretty inert stuff, refractory. Melts above 2000 °C. Quite common, actually.

The problem is not the temperature. That's a limit we don't have to deal with because there simply aren't materials capable of remaining solid at 7000 °C.

It's the heat. The heat creeps in and elevates the temperature, melting polymers in electronics. The insulating lining would include asbestos and similar stuff.

If you want a probe for a gas giant, you have to go Venus style. Special electronics capable of working at 300-400 °C, so it would still work while the outside is beggining to melt.

[Idobox]

Mostly, the pictures would be boring.

What you want is a thermometer, a barometer and a spectroscope. Maybe a Pitot tube, but you could probably infer the wind speed from orbit by measuring the movements of the probe.

Temperature would become a problem before pressure does. Semiconductor would die rather quickly, but vacuum tubes will work as long as the metal they're made of stands. For electric insulation, you'd have to use ceramics or carbon, asbestos melts at 1500°C, carbon at 3500°C and tantalum hafnium carbide slightly higher, the metal would be tungsten at 3700K.

Batteries will be a tougher problem, one I don't know how to address: chemical batteries will die very quickly, and flywheels won't be an option because the magnets will be destroyed by heat. Maybe super-capacitors?

The other option would be to plunge quickly, and to have a nice heat insulation, keeping the electronics and instruments alive as long as the outer shell survives (3500-4000K will be the limit)

[lajoswinkler]

There can be a supply of water inside. It has a huge thermal capacity and can limit the temperature of the probe at 100 °C as long as there's some of it in the cooler. As the probe goes down, the water circulates and the vapor is released outside, carrying heat away from the electronics.

Of course, you wouldn't send a basketball-sized probe. It should be a fairly large sphere, 2 m in diameter perhaps. It's not that difficult. There are more factors to account for than just pressure and temperature, otherwise touching a lighter flame would destroy your hand instantly.

[Lukaszenko]

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?

[dansmithers]

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?

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

[magnemoe]

Mostly, the pictures would be boring.

What you want is a thermometer, a barometer and a spectroscope. Maybe a Pitot tube, but you could probably infer the wind speed from orbit by measuring the movements of the probe.

Temperature would become a problem before pressure does. Semiconductor would die rather quickly, but vacuum tubes will work as long as the metal they're made of stands. For electric insulation, you'd have to use ceramics or carbon, asbestos melts at 1500°C, carbon at 3500°C and tantalum hafnium carbide slightly higher, the metal would be tungsten at 3700K.

Batteries will be a tougher problem, one I don't know how to address: chemical batteries will die very quickly, and flywheels won't be an option because the magnets will be destroyed by heat. Maybe super-capacitors?

The other option would be to plunge quickly, and to have a nice heat insulation, keeping the electronics and instruments alive as long as the outer shell survives (3500-4000K will be the limit)

You would protect the electronic with evaporation, perhaps not water but something else, cameras is nice but would be a separate sub system as they only have to last while its light.

However how to protect the spectrometer most of all, thermometer and barometer can be done indirectly, perhaps use the door idea for camera to protect it and do samples at intervals.

Still remember the shock I got then I found that Jool core was black at 3km, far more so then it was transparent and I could see Laythe down there.

[cantab]

There can be a supply of water inside. It has a huge thermal capacity and can limit the temperature of the probe at 100 °C as long as there's some of it in the cooler. As the probe goes down, the water circulates and the vapor is released outside, carrying heat away from the electronics.

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.