Doing a quick and dirty extrapolation from that chart, at -264 km you’d be at approx 10^9 pascals pressure (10000 atmospheres) but only about 800 kelvin.
We could probably build a suit to withstand 800 kelvin for a while, but could we build a suit to withstand 10,000 atmospheres pressure? My guess from that chart is you’d be squashed before you fried.
How does water get denser at all? I thought it was an incompressible fluid.
The characteristic of liquid is that it is virtually incompressible. So in the depths of the ocean, or in Jupiter’s non-surface, you would have the gaseous parts squashed flat - lungs, sinuses, inner ear, miscellaneous bubbles in the intestines… But your basic body would remain intact.
Whether we’re talking body or scrap metal, it’s still denser than water and sinks in the ocean. Metal (solid) also does not compress (significantly), so relatively the density ratios are still the same - metal and bodies sink in water.
Compressed hydrogen or liquid hydrogen or supercritical fluid hydrogen is still much less dense than organic or regular metal materials - so you keep sinking.
Note the extreme prssure and temperature at depth in Jupiter’s “oceans”. This is where the non-hydrogen tends to accumulate. Life (Jim, but not as we know it) is made up of complex chains of molecules. In the case of carbon organics, the ones that we use require a very precise range to remain intact and perform the functions that keep us alive (plus we need a specific mix in our environment).
The theory is the convection and general environment deep in Jupiter is not stable or friendly enough to allow the complex molecules, whatever they are based on, to form and remain intact and functioning. There have been scince fiction stories of life floating in the clouds of Jupiter and such, but note the earlier post that much of the non-hydrogen elements precipitate down out of the upper atmosphere.
Finally, gravity does not increase as you descend. Once you are well towards the core, gravity becomes less. In fact, a though experiment will show that in the exact center, you sould be weightless.
FYI, according to several sources, including this one, the gravity of Jupiter is about 2.5 times Earth’s, so if you were in a suit that could stand the pressure, the gravity alone wouldn’t crush you down to a pancake. Military pilots are routinely subjected to higher g forces than that while maneuvering their planes.
Clarke also wrote A Meeting with Medusa, a novella about a manned descent into Jupiter’s atmosphere. In the story, the craft was essentially a hot-air balloon, with rockets in order to ascend and return to an orbiting spacecraft.
“Incompressible” is an oversimplification, like clearly dividing things into solid, liquid and gas, saying solids have fixed shapes, etc.
I thought water would certainly have some amount of ‘free space’ in it under the conditions we normally experience it. But I am curious what is happening under great pressure. A 6% density increase isn’t all that great, but is the pressure just squeezing it down to maximum density at that point, or is there some other change?
It’s progressive. Water (and other liquids) is incompressible in the same way that steel is inflexible - which is to say that it is, in fact, very slightly compressible. Not enough to matter for most practical purposes (which is why high school science teachers can safely teach that water is incompressible), but for some purposes (e.g. density calculations at very high pressures), it matters. Oils have a greater compressibiliy (lower bulk modulus) than water, so the compressibility matters at lower pressures I’ve worked with 7,000-psi hydraulic systems where the choice of hydraulic fluid had a measurable effect on efficiency: the fluid with greater compressibility fostered lower efficiencies. Liquid compressibility is also a factor in the power consumption of the latest and greatest diesel injector pumps, which operate at pressures upwards of 25,000 psi.
Bulk modulus tends to increase (i.e. compressibility tends to decrease) as you move to higher and higher pressures. Take water from 14.7 psi to 16,000 psi, and you get about 6% increase in density; take the pressure from 16,000 to 32,000 psi, and you won’t see another 6% increase; you might see (shot in the dark here) a 4% increase.
Poul Anderson also did the short story “Call me Joe” (“Avatar” used the same idea) which involves Jupiter.
Asimov produced at least two stories connected to the subject of Jupiter’s surface conditions.
In Victory Unintentional, a humorous comedy, three very special robots are sent to Jupiter to attempt to persuade a very xenophobic and aggressive race that they should have peaceful relations with the humans on Ganymede and “the inner worlds” rather than wage war against them.
I say “special” because this is one of the few robot stories with a departure from his more typical robots. These robots are very squat and non-humanoid in appeareance, besides being virtually indestuctible in materials and design.
I recommend reading this short story, appearing in “The Rest of the Robots” and elsewhere, because it is so funny, with a very surprising ending.
There is a non-robotic prequel *Not Final! *is which the xenophobia of the Jovians is discovered, but at first the supposed inability of anyone to develop a stable atmosphere-containg force-field leads the humans to breath a sigh of relief.
Unfortunately, a technician discovers a way aroung the supposed invincible production barrier and the theoreticians and leaders realize that they cannot be sure that the Jovians will not be able to duplicate the discovery, and that leads them back to their original fears.
ISTR an extensive discussion of why the Jovians could not be defeated in war, nor could a preemptive genocidal strike be carried out against them.
The gravity of the core is zero at the exact centre; at which distance from the core do you calculate the gravity to be 100,000 times that of Earth?
If the solid core has a mass of 10 x Earth (as seems likely) and the average density of the compressed core is ten times that of our planet, so that the core is the same size as the Earth, then the gravity will only be ten gees. Even though the core is compressed very considerably I doubt it will be much more than ten times as dense as the average density of the Earth.
Tidal forces are just the difference between the force of gravity at your head and at your feet. Since these are only 6 feet apart at any given time, I can’t imagine you would notice any tidal forces during your descent.
You can actually show that the gravitational tidal forces between your head and your feet as you fall freely through the fluid will be proportional to the density at that level, assuming that the body is spherically symmetric and you’re falling in feet-first. The density of Jupiter’s core isn’t known, but even if Jupiter’s core is as dense as the core of the Sun (which it probably isn’t), the differential acceleration between your head and your feet is about 0.2 mm/s[sup]2[/sup]. That’s a hundred time larger than the tidal effect between your head and your feet here on Earth’s surface, but you’d still never notice it.