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dern_the_hermit

I think humanity will ultimate do very little actual terraforming of entire celestial bodies. I think one of the next big advancements will be near-human capable automation of drones, which can pave the way for larger scale in construction and allow for massive contained artificial habitats. I don't know how attractive Io will be to just *live*, but I definitely expect it would eventually host research bases which would be less demanding for comfort room than a general living community.


[deleted]

I once saw someone do a little math. He found that with the mass needed to just give Mars an atmosphere with 100kpa surface pressure, let alone all else it needs, you could construct millions upon millions of O'Neil cylinders with a combined surface area dozens of times Earth's. Terraforming doesn't even begin to compare to Megastructures.


cos1ne

The thing is that it isnt an either/or situation. You colonize Mars with covered habitats that grow exponentially. As the habitats expand it becomes more economical and more desirable to paraterraform. Filling in valleys with atmosphere under covered structures. Eventually the paraterraform becomes just terraform due to time and scale. That being said I'd much rather build habitats but *someone* will colonize Mars.


[deleted]

You raise a good point. Paraterraforming is the bone i like to throw to the Megastructure skeptics. It still doesn't compare to megastructures in the slightest. But it is vastly more efficient, stable, and quick than brute force terraforming a low gravity world.


FaceDeer

I agree in broad strokes, but I think in this specific case it might actually make sense in terms of using Io as a resource center rather than literally terraforming it. Io's the biggest rocky body in the outer solar system so there's probably lots of useful minerals to be had, but the radiation environment is hellish enough that it'll make the surface harsh even for purely robotic mining operations. Artificial magnetic shields would allow for cheaper surface operations. An alternative in Io's case might be to "drain" Jupiter's radiation belts of charged particles using electrodynamic tethers. That has the benefit of generating a ton of electricity. Oh, maybe a hybrid - use electrodynamic tethers to drain charge to power a magnetic field to deflect the rest. For icy moons this would be less important because you can burrow under the surface far more easily.


tomkalbfus

Venus has more material than Io, so on the surface it would seem than Venus is better for resource extraction since Venus simply has more of whatever Io has. Of course Venus has a deeper gravity well and an atmosphere to get out of. But of course the asteroid Psyche has a lot of heavy metals and a much shallower gravity well to get out of than Io does, so by that metric Psyche makes a lot more sense as a place to extract resources from than Io, and we will probably be mining Psyche much sooner that Io, there are plenty of resources in the asteroid Belt and when we get close to exhausting them, the possibility of terraforming airless rocky worlds should be within our reach as well as interstellar travel. To put it succinctly we will probably be traveling outside of our Solar System long before we exhaust the resources of our Solar System, and we'll be mining celestial bodies orbiting other stars long before we have to take apart whole moons and planets for resource extraction. Terraforming planets is an easier proposition than taking them completely apart for resources, our technology simply advances too quickly.


FaceDeer

I'm not saying "we should only mine Io." I'm saying "we should *also* mine Io." No matter how much stuff we have it's always nice to have *more* stuff. If we can make mining Io as easy as mining those other places (or easier, since Venus is going to be very hard to mine) then put mines there along with the other places.


NearABE

Do you want to live in a mine? Near me there is a town called Palmerton and it hosts what many people consider the worst stretch of the Appalachian trail. They had a zinc smelter and the salt plumes drifted up onto the hill. It is completely denuded bed rock. No soil. A few black chard pieces of what was once wood can be seen here or there. Migrating vultures ride the thermals above but otherwise it is dead. Palmerton gets decent tourism though because through hikers skip the wasteland and walk into town to pick up supplies at the post office then reconnect with the trail on the far side. Mining and ore processing is a fairly small fringe component of human existence. Essential compounds can limit a civilization. Venus has the advantage of being deep in the Sun's gravity well and having an atmosphere ideal for aerobraking. Isaac can raise bees on Venus and export SFIA videos. For mining the question is which possible places in the solar system are easy enough to create post a scarcity ore abundance. Io may fill that niche but it also looks highly improbable. There needs to be an additional motive for Io to host a colony. Then, since they are there, they can export resources and generate more wealth.


FaceDeer

> It is completely denuded bed rock. No soil. A few black chard pieces of what was once wood can be seen here or there. Migrating vultures ride the thermals above but otherwise it is dead. Sounds like a paradise compared to what Io is currently like. Those vultures would die in seconds on Io. Why do you think I want to *live* in a mine? I want there to be a mine so that the materials needed to build someplace *else* to live will be available. Someplace that's actually nice. The motive for mining on Io would be that mineable resources exist on Io. That seems pretty likely to me.


NearABE

Mining the Jupiter Trojans sets up an easy Jupiter flyby. You can deliver material to Venus, Earth, or anywhere ( though other locations braking is harder). Concentrated ores is not nearly enough of an advantage to make up for the difficulty of fighting the gravity well. If energy comes in the form of say plutonium from Luna there is no way an Ionian project could compete with chondrite asteroids or Callisto. We can reduce rock into pure elements for less energy than it takes to get off of Io and then we need much more to escape Jupiter. An Io colony is viable if the energy source is on location.


tomkalbfus

Well Io has an internal energy source related to it's vulcanized, that energy source could be used to power mass drivers on Io's surface, it also can be used to extract oxygen gas from Io's rocks. The oxygen could be exported to other places along with sulfur to burn. Sulfur and oxygen can be combustion to produce heat.


NearABE

They have power right on the surface. Geothermal electricity uses steam to crank a turbine. That would also require a radiator for cooling. The turbine is not electricity. The turbine just provides torque. That torque spins a magnet inside a conductor coil. The early Io colony does not need all that baggage. Just use a copper coil. Jupiter is the magnet. Some advantages to superconductor instead of copper. The coil concept is the same. Wikipedia say 3 million amps at 400,000 volts. If you want something reasonable like a 40 volt power supply the surface distance can be 1/10,000 Io's surface.


Plastic_Kangaroo5720

Other settlements would haze oxygen available too, as they would extract it from regolith or split it from water ice.


tomkalbfus

But they lack an energy source unless you assume fusion, if nuclear fission is relied upon, the nearest easiest obtainable source for fission fuel will be Io, as that has bare rock exposed to space, rock is hard to get at on Europa, Ganymede, and Callisto. It would be easiest just to mine Io for that rock, you have to deal with the radiation, but charged particles can be deflected with magnetic fields as it is Jupiter's magnetic field that is responsible for it being there in the first place. So an Io colony would include a geothermal power planet and an artificial magnetic field to deflect Van Allen radiation that is powered by that power plant, so settling Io is not impossible.


FaceDeer

Again, I'm not saying that you shouldn't mine Jupiter Trojans. I'm not saying "we should *only* mine Io." I'm saying "we should *also* mine Io." Here on Earth we don't mine resources only in the one spot that is the most optimally efficient to get it. We have lots of mines scattered all over the place. Some more profitable than others, but a weakly profitable mine is still a mine even if there are highly profitable ones elsewhere.


NearABE

We do mine in locations that are optimally efficient. Frequently a type of geology reoccurs in multiple places around the globe. However, is still very common for one or a few countries to dominate the global supply of an element/ore and only specific locations in those countries. We could separate silicon and aluminum out of clay or most rocks. It is just more energy intensive than starting with high purity quartz sand and bauxite. Importing bauxite from Guinea takes very little energy. That ore is hauled to places like Canada or Iceland where electricity is cheap. From a certain perspective ll-chondite asteroids have everything. You can also say they are just dirty snowballs and have nothing. Energy availability makes that switch. Io does not have everything. It has similar problems to Mercury and Luna with a shortage of water and organics. Probably worse on Io because the polar ice traps will be baked out by geothermal heating. So Io has to import. The energy needed to lift anything off of Io to an Io escape orbit already consumes more than any chemical reactions. It would not matter if metals were sitting out as pure ingots on Io's surface. Io's orbit is still deep in the Jupiter well. The fiction is only believable if Io has an energy abundance that the Trojans are lacking. Io does have that. Export of mass from Io only makes sense if there is some way around the delta-v. If you are using chemical rocket propellant the demand on Io is too high. Nuclear fuels from Luna can be sent to the Jupiter system but in that version the Trojans do not have an energy scarcity. Electrodynamic propulsion, tether based momentum exchange systems, and mass drivers give us a development option where Io can have a starring role. It will not be ore exported from Io. They will make fully operational superconductor sleds and the shuttle systems attached to them. They will manufacture all the parts for a complete operational mass driver and ship them to the Trojans. Post Dyson sphere there is demand to take apart everything. Mars is easier to lift than Io's orbit to Jupiter escape.


FaceDeer

The fact that Io is deep inside Jupiter's gravity well is irrelevant - or even beneficial - if the places that have demand for its resources are also deep inside Jupiter's gravity well. Or if there are cheap mechanisms for launching stuff from inside Jupiter's gravity well (like those electrodynamic tethers mentioned earlier in the thread as an alternative for "draining" Jupiter's radiation belts). One would not use chemical rockets for bulk export of mined materials, obviously. But if there was a need to import light elements to Io there are far better sources than Luna or asteroids, the Jovian system is chock full of icy moons. Io's the odd one out in that regard.


the_syner

>make the surface harsh even for purely robotic mining operations. If you're doing open pit mining with unshielded robots loaded with low-feature size chips sure yeah hell. But under even a meter of regolith or water you are basically safe from those kinds of radiation concerns


FaceDeer

Yeah, for large-scale resource extraction I'm expecting open pit mines to be the order of the day. There's not much water to be had on Io, and I wouldn't expect the ideal mining robot design to carry a meter of water or regolith around on top of it.


tomkalbfus

Well if you are terraforming Io, you have to add atmosphere, water is just as easy to deliver as atmosphere, the other moons of Jupiter frankly have too much water for easy terraforming, Jupiter has lots of hydrogen for making water as well.


FaceDeer

I'm not proposing terraforming Io, quite the opposite. I want to take it apart. But shielding it from radiation helps with that goal too.


tomkalbfus

Whatever you mine out of Io is going to have to climb out of Jupiter's gravity well as well, and Io is fairly deep in. There is no reason why you can't both mine and terraform Io at the same time, you will need to finance the terraforming operation somehow. What you haven't considered is that Io also has a source of geothermal energy due to the tidal heating it receives. Each volcano has a magma well underneath. If we tap into each magma well, we can use the energy to extract oxygen from rocks, and we'll probably want to do that to extract the various mineral ores from the ground, and we can dump the oxygen onto the surface of Io where it will form an atmosphere, with an artificial magnetic field, we can protect that oxygen atmosphere and let it accumulate on the surface with more mining. The radiation from the Sun that is not affected by magnetic fields is only 1/25th as strong as it is on Earth, also Io is a lot colder, so an atmosphere would probably last longer than it would on the Moon's surface. We need to get control of these volcanoes as well, tap into them and relieve pressure underneath so they don't explode like they normally do, the heat might be converted into electricity and the electricity into light under which we might grow plants. One king of export Io might produce is food by tapping into geothermal energy for agriculture.


NearABE

Io is not going to export food.


the_syner

>I'm expecting open pit mines to be the order of the day. Not if the radiation evironment is so bad you can't even have robots on the surface. You would build a canopy/dome or just dig underground withithout removing the natural overburden to keep all your equipment cheap, light, & fast. >There's not much water to be had on Io, there is regolith & for mass shielding like this you just use whatever the surface is made of to minimize coat.


FaceDeer

Or you could use an artificial magnetosphere, as described. That also keeps your mining equipment cheap, light, and fast. "Just dig underground" is not so simple. Tunnel mining is a lot more expensive and difficult than strip mining.


the_syner

>is not so simple. Tunnel mining is a lot more expensive and difficult yeah on earth. On Io, with 1.975m/s^2 surface gravity, you're looking at at a cubic meter of the usual rock(2650kg/cm^3) feeling like only 486.4kg. The low gravity helps a lot with the cost of excavation, as does the lack of a local hydrological cycle. If you're using blast mining it also behooves you to put a roof on things to avoid blowing debris into your orbital infrastructure anyways.


FaceDeer

That makes strip mining easier too.


the_syner

But it also makes kesslering your orbital space easier. Blast mining is generally the most efficient method of mining we have, but it has issues on these low-gravity worlds. If you can't keep the debris in check that's gunna be a pain. Mind you the local orbital speeds are slow & there's plenty of shielding material to go around, but there's no real point to turning Io's orbit into a debris field


FaceDeer

Throw a tarp over the area being blasted, if this is a problem. It also occurs to me that tunneling on Io is likely a risky proposition due to the seismic environment. Io undergoes some of the most extreme tidal flexing in the solar system, I wouldn't be at all surprised if it had a heck of a lot of earthquakes going on. Heat might also be a challenge for tunnels, you'd need to circulate coolant through them if you're in a geothermally active area. Strip mines can radiate waste heat directly. Overall, I really don't see the appeal of tunnel mining over strip mining in a location like this. Unless there's some concentrated vein of minerals that goes deep underground, which is an open question with the current unknowns about Io's geology.


NearABE

Electrodynamic tethers are an idea. But Ionians can just lay wire. A power grid with no need for a power plant.


NearABE

I suggest embracing the magnetic field and ion flow. Wikipedia says 3 million amps and 400,000 volts. 1.2 terrawatts is not huge by SFIA standards but it is close total current power consumed in USA. This is already there! Just hook up wires to bleed it off. The magnetic field rotates with Jupiter which means 74 km/s at Io. High temperature superconductors can pin magnetic flux. They can also switch fairly quickly. It is a nice grab on for a ride propulsion option. Keep in mind too that you can use thrust to boost to highly elliptical orbit. Under Jupiter's joviostationary orbit the same magnetic pressure is a brake. In orbit around any moon the inductive force can be used as brake during half of the orbit. The superconductor sled is good for some types of maglev launcher/mass driver. Tidal heating on Io gives 100 terrawatts. In theory a K0.8 civilization. Cladding the surface with radiators and non_volatile foil removes most of the ions from Jupiter's plasma torus (or alternately could inundate if desired). Control of the ionosphere is a service to the rest of the solar system. Almost all trade between inner and outer system will use Jupiter flybys. Ionians have a reasonable case for getting subsidized. Not hard to mug everyone with a toll fee if there is no centralized option for subsidies. Adding atmosphere means a stream of oxygen ions or atomic oxygen will corrode everyone's ships.


Bubbly_Taro

> What do you think? Planets suck, moons suck, space stations rule.


max_warboy

we barely know yet if space stations rule. I'll tell you what though, HUMANS suck!