A drill made mostly of ice

[Catastrophe]

OK, I look forward to that!

 

[billslugg]

I would go with a lander that dropped a probe onto the icy surface which then melted its way down to the ocean below unreeling a fiber optic communication cable as it went. I would use a plutonium-238 radioisotope heat generator. I could also provide power. The ice would freeze behind it but it would not be designed to return. A one way trip. The ice layer at the south pole region of Enceladus is thought to be 40 km thick with a 10 km thick ocean layer underneath. If a fiber optic cable had but a thin gold coating to keep the light inside it, then its thickness might only be 100 microns. Fifty km of 100 micron fiber could be held in a box 162x162x162 mm. About the size of a loaf of bread.

 

[Phillip Huggan]

"Would you rather stand on a steel platform, supported by steel struts, 10,000 feet up in the air, or on an ice platform supported by ice? And then add a 10 ton weight to your platform?...Cat "

10 tons Earth or 10 tons Callisto? Containing compressed gases, a fibre outer shell is pre-stressed to start out at the shape it will be being pressurized by a full CNG load. In a vacuum or low pressure cylinder, it will still be in (hoop) tension, whereas the inner metal liner will be flexing and compressing inwards. It isn't a uniform delamination, or modelled at all. Oppositely, when contents under pressure, the metal (or hard plastic) is modelled to uniformly follow a curve where it elastically deforms towards the fibre and eventually plastically deforms. But the impact with the fibre also plastically deforms it. Not modelled 2022. The curve is maybe not even a function on a graph. Smaller than 4mm metal width, the uniform plastic/elastic curve no longer applies and it will stay elastic or earlier become plastic, depending on finer grained materials properties.

I envision upgrading Orion with sapphire; 4-10x the interior volume. Landing Above a meteorite frozen 200 meters deep. Digging 10 meters deep fast. Bringing some of the compartments added to Orion to become mine-huts 10 meters below the surface in ice. An ice drill requires two meters of horizontal clearances, the mine shaft being a meter. A 3 metre tall cylinder one meter radius, melted, widens the bore hole for ice drill. A metal racking hung at the ceiling of the hollow can-in-ice, used to rack the drill to. The silhoutte is a room 10 meters down, then a shaft with tiny rooms along the way until the ores. After that, all sorts of fancy scapes can be constructed assuming a geologically bad event doesn't happen. You can be up in the air but radiation protection of some sort is needed from this planet/Io. The surface ship gets damaged while (table-top) milling ore. Steel would rust but Al and Pb shouldn't as drills.

 

[Catastrophe]

"Steel would rust but Al and Pb shouldn't as drills."

I thought the suggestion was about local ice?

Lead is pretty dense - heavier than steel.

Back to the point. Transport of steel drills is much lighter than transport of entire factories and personnel and life support for same - really no contest! Aluminium factories included.

Cat

 

[Phillip Huggan]

Watch a Vacuum Chamber Sublimate Snow Into Vapor

When snow melts at such a low pressure point, it can't turn into liquid.

www.popularmechanics.com

Snow in a vacuum chamber. Maybe the heat from the facilities can be made not to rust buildings. In a drill hole, there is likely enough H20 ice to rust stuff in there. You could vent it to the surface from the drill hole.
I'm worried about the drill catching in the ice, perhaps on a frozen comet fragment or some gravel laced with ore minerals. The softest drill may be plastic or rubber. Then lead. Metal. And crystals hardest common. One of ten things to worry about while cold drilling.
I assume the people will be there as workers eventually just for the medical science; knowing how carcinogenic the radiation is there paradoxically might be worth an early clinic there.

 

[Catastrophe]

Billslugg, is the heating method you describe sufficient to access water, which is the object of the exercise? That wire sounds very thin.

Cat

 

[billslugg]

The heating is done by a radioactive source, Plutonium-238, which is currently used to power spacecraft going to the outskirts of the solar system. The thin cable is used only to transmit information back and forth to the lander sitting on the surface.

 

[suneritz]

Hypothetically speaking, to tunnel through 40km of high pressure constantly chilled ice on Enchiladas, you need not a fission device but a fusion one. Something like a superconducting magnet held miniature Sun the size of bowling ball but heavier. It would probably come with wireless “treki” communicator instead of a wire and could go down or up(antigravity) in a low angle spiraling rolling motion. Sounds completely unrealistic but not if we’ve already had a fusion power, which could be just around the corner or two? Thanks

 

[Catastrophe]

But, if you have nuclear energy available, you can melt the surface ice to get your water - especially the water for "industrial" purposes.

billslugg then has the answer.

Cat

P.S. "There never was a good war, or a bad peace."

 

[billslugg]

Hypothetically speaking, to tunnel through 40km of high pressure constantly chilled ice on Enchiladas, you need not a fission device but a fusion one.

Let us look at some numbers. Make some assumptions.
Diameter of the probe that melts its way down = 16 cm
Frontal area of probe = (16/2)^2 x pi = 200 cm^2 = .02 m^2
Distance it must melt through the ice = 40 km = 40,000 m
Amount of kilograms of ice that must be melted =
40,000 meters x .02 = 800 m^3 = 800,000 kg

Temperature of the ice = -200°C
Specific heat of ice = 2.1 kJ/kg/°C
Heat of fusion of ice = 333 kJ/kg

Heat required to raise ice to the melting point = 800,000 x 200 x 2.1 = 3.3e6 kJ
Heat required to melt the ice = 800,000 kg x 333 kJ/kg = 2.6e8 kJ
Total heat requirement = 2.63e8 kJ

Time allowed for the descent = one month = 720 hours =2.6e6 seconds
Power requirement of radioactive heat source = 2.63e8 / 2.6e6 = 100 kW

A 100kW radioisotope generator made of plutonium-238, that cannot be turned off, is a bit large in my estimation. I would tend to reduce it to 10 kW and then allow ten months for the descent.

Or one might consider a fissile uranium source that is kept in two pieces until the heat is needed.

 

[Catastrophe]

Ahem. Excuse me but:

"if you have nuclear energy available, you can melt the surface ice to get your water - especially the water for "industrial" purposes.

billslugg then has the answer.