True that. Let’s them be those meek who shall inherit the Earth.
Mars has no magnetosphere, so unless you’ve got a plan for creating a planetary dynamo, it’ll never be very Earthlike.
He envisions using Mars’ moons, Phobos and Deimos, as preliminary stepping stones for astronauts.
I wonder why? They’re even colder, less watery, and less pressurized than Mars.
I guess maybe it’s because Mars’ gravity well is a lot harder to escape than its moons’, but if that’s what it is, I’m okay with waiting to launch our Mars colony until we can manage to build a vaguely reliable back-from-Mars rocket.
There have been a lot of voyages of exploration where the ship ended up not being able to make the return trip, but few if any that were launched with the expectation that it wouldn’t, and certainly never to places where the explorers knew for a fact they wouldn’t be able to fix anything that had broken once they landed.
True. It will be losing atmosphere and so on.
The question is, can it be sufficiently Earth-like to live on with reasonable comfort for reasonable time? Can the losses be replenished fast enough?
Look at them as convenient stations already in orbit, ready to build resource depots and a spaceshipyard on. You need a lot of material to get to Earth (or to other planets). The gravity well is a bitch. Getting a fleet of smaller rockets getting the gear to the depot, and building the main thing there, sounds easier than building one big rocket. A failure of one-of-many is also easier to rectify than a failure of the-only-one.
Similarly, for receiving the cargo from other planets there is no need for atmospheric reentry shields.
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Well, given the case against Mars, I would prefer to colonize and industrialize first Luna, then Ceres, and then Titan. Why drop back down a gravity well after working so hard to get out of one? Why terraform a planet when there are perfectly good moons laying around?
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Luna is a fairly good bet, it’s just next door. The slow rotation is a bitch that will cause problems with thermal loading of any surface structures. And the gravity is low.
Ceres is annoyingly small. The low gravity is an advantage, but also a disadvantage.
Titan has even lower gravity than Moon. Again, good or bad. The major good here is the stores of methane plus the water-ice for production of oxygen; a methane-oxygen rocket is possible and in-situ manufacture of fuel is a major advantage.
Mars has more gravity, which may be beneficial for long term occupants. There is also possibility for the planet to keep enough atmosphere for long enough for unaided breathing.
I’d say, all the places have their advantages and disadvantages. Let’s build all the bases, each for a different purpose.
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Sunlight’s getting kind of dim by the time you get that far out. Mine the asteroids for thorium?
Also, Titan is in a gravity well itself, the one of its giant mother planet.
But, yeah, it has lots of the right kind of resources, right on its surface.
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Certainly. Assuming we don’t have good fusion by then yet. I’d see it as compact molten salt thorium cycle reactors with online fuel reprocessing. If electromagnetic pumping is used, there may not have to be significant moving parts in the loop, which would greatly improve reliability. The problem so far is with corrosion resistance of existing metals to molten salts; maybe some sort of self-healing ceramics/carbon-based composite either in bulk or as a liner?
True, forgot about that one. As easy as forgetting about the gravity well of the Sun.
Oxygen and hydrogen to get from ice, enough methane to fill several lakes, nitrogen a plenty, but a dearth of metals and heavier elements in general… But that’s what asteroids are for.
But stay the fuck away from Europa!
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Ah, okay, that makes sense. I think I was interpreting it along the lines of “let’s see if we can handle the little baby Marses before we set foot on the real thing,” which didn’t sound very astronaut-y.
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Though obviously, if you are already in orbit, a wimpy little ion drive can lift you. You don’t need the kind of brute force we require to push aside tons of air (per second) and reach orbit from a dead stop at 1G…
Assuming fusion proves to be intractable, might be worthwhile to build enough of a fission pile to make Pu238 or some such thing, to power the ion drives from a reliable RTG.
One obvious advantage of asteroid-mining is that very few people will be around to care what happens to your fission reactor. If it goes full China-syndrome and sinks to the center of the asteroid, well, so what? You’ll maybe have a slightly warmer asteroid. Might even find an application as a mining tehnique – just melt the thing, and skim off whatever metals you want. Another non-issue in space could be radioactive steel. Perfectly acceptable in a robotic craft, and a matter of shielding otherwise.
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Also forgot about this, thanks. And then there are the chaotic orbits where we can gain quite some energy just by being at the right moment at the right place so we can use the gravity tug of another body.
There are major shortages of Pu238. I’d suggest to go for yet better power density with more available materials, namely for a fission reactor. E.g. the TOPAZ nuclear reactor our brothers Russians developed and successfully flew.
This is an actively researched area.
China Syndrome is quite a crap hypothesis. The mass of the fuel will get diluted pretty soon, and the heat production, exponentially falling, will soon stop being sufficient to melt the materials. See also corium.
Potential issues with inducing errors in electronics and increasing background noise for some sensors, otherwise true.
Point being, all the wacky but real tech we can’t use here on Earth, like pertechnetate anticorrosion coatings, can be used in space. They already shield, or make otherwise rad-resistant electronics for space. We would never have gotten probe to Pluto without doing that.
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