New Mars Forums

So, not a cloud after all? Still a torus. Or is this just the inner Hills cloud?

I wonder how many are dwarf planets...

Hmm. Close to the major population centre and with few resources of its own but plentiful energy... Luna sounds more like the Netherlands than Mars does.

The amount of CO2 dissolved in water depends on the CO2 partial pressure above it. If we're compressing air, we might as well pass it over a film of water to extract the CO2 for uses such as synfuel. We don't even need to heat the water up to extract the CO2, since reducing the pressure will cause it to outgas.

I've considered gas centrifuges too, but that seems like it would be far less energy efficient than the 1 kWh/kg current systems achieved. But now I'm wondering if one could be used to force the CO2 into a layer of water in a continuous process.

Rain contains dissolved CO2 collected on the way down -- An estimate on the rainout of atmospheric CO2 The estimated concentration is pretty low though, at 5e-4 g/L. However, rain droplets are fairly large. If we sprayed a fine mist into a chamber of air, could we disslolve a lot more due to the greater surface area? Moving liquid through air seems like it should take significantly less energy than moving air through liquid...

Could of course also do this with Calcium Oxide, if the air is dried first. Then solar thermal to regenerate. AFAICT what is driving the expense of direct air capture isn't energy usage; current systems cost about 1 MWHr/Tonne, whilst achieving costs of $250+/Tonne of captured CO2. Capital costs seem to be driving the expense? We need very cheap systems that can run on cheap intermittent power.

(Copying from another thread)

One of the most abundant substances available for building habitats out of is ice. Certainly useful as a shield. We've discussed building shellworlds with it, relying on self gravitation IIRC; whilst its (probably...?) not strong enough in tension for anything useful, in compression very cold ice can be comparable to concrete.

Dwarf planets are good places for centrifuge towns, sunk into the ground with angled floors. Imagine an entire world tiled in such hexagons. The planet provides a very large amount of mass to anchor spinning habitats and prevent tumbling, and allows for shielded rail (and foot) transport between them.

Or even a hollow one, formed from a vast geodesic sphere used to connect centrifuge modules together and covered in ice for protection, perhaps with a layer of soil and a thin atmosphere for a microgravity ecology, definitely with a magnetosphere. The comet shellworld idea except we're incorporating the habs into the shell. If they're say 200m long 100m diameter, each hab has about six hectares of surface area, whilst taking up idk two hectares of the shell (the ends are around 0.8 Ha, I'm not trying for precise design here).

A shellworld that's 100km across will have a surface area of 31,000 km^2  approximately 100,000km^2 of habitat area whilst looking suitably planet like from the spacecraft our intrepid heroes are in tongue  That is half the size of Great Britain, admittedly broken into chunks; the ideal size per tile is probably 10x bigger. Though there would be less surface area in that case if length is not proportionally increased -- tile size grows with the square of radius, internal surface growth is linear). If they are say 500m rings 1km across, thats 150 Ha per hab (a good sized small town -- city even, if we put our gardens on the room and in basements) but overall we're down to about 24,000km^2. If we increase length to 2km -- proper Onhyl cylinder time -- we're back to our space England (okay, three quarter sized Space England) with 6km^2 chunks. Alas, still not large enough for reintroducing the wolf, but I think foxes might be okay.

Tbh I suspect its the power loss from radiation and conduction that would kill this. Its possible that it would be manageable for very thin (but still useful) atmospheres, such as needed to handle micrometeorites, or for capping the atmosphere on low gravity worlds such as Ceres. If used to deal with atmospheric escape, it may be that we'd still have years of atmosphere left to effect a fix should the system fail, the field is there to extend those years indefinitely.

Could prove useful in the Saturn system. Six worlds comparable to Ceres. Uranus has five.

Been playing X2 and X3 (Reunion) (space 4X games) recently, and it got me thinking about the idea of the gates collecting a (very tenuous) atmosphere that results in ships having maximum speeds and continuos thrust and other such tropes.

Anyway, the relevance here is, what might travel be like within such a magnetosphere containing say an atmosphere equivalent to 60km here on Earth? Pretty much vacuum from a human POV, but that's still enough drag that nothing can orbit there. There would be far more mass available for an ionocraft such as the dipole drive to make use of.

Then I got thinking about the highways of X4 and started to wonder about linking magnetospheres into a torus...

How tricky would it be for a stationary platform to focus sunlight into a beam with such optics? If it can be directly used, rather than requiring conversion to electricity then to e.g. a maser to transmit power, the system should be less complex (efficiency is a far less pressing issue in this case, given how much sunlight is available). Stationary platforms will not be so mass constrained, so they can be scaled up to ensure the same beam intensity whether around Terra or out at the Trojans or by Saturn. Illuminating a ship with 10kW/m^2 of sunlight should give pretty good power to mass ratio for its collection system...

The bigger issue is that compression requires heavy tanks. Maybe carbon nanotubes have changed that.

The other option is to use something like ammonia that can be liquified. Or ethane, even, though that doesn't provide any lift its about the same density as air.

Carnivores are pretty resistant to prion disease, as you'd expect from animals that subsist on eating other animals. Some humans are resistsnt to BSE (mad cow disease), which is a good thing because the British government almost killed the country off in the 90s, something we ought to have had executions for. A single amino acid substitution seems to do the trick , though you have to be homozygous for the resistance allele in order to be fully protected; in heterozygotes, there seems to be a delaying effect, we've had people dying from BSE a decade or so afterwards.

Prions are nasty things. Good candidate though for the poison in a retelling of Sleeping Beauty IN SPACE! Suspended animation should slow the spread, and 100 years of medical advancement might be able to treat it...

A hovercraft might be able to do it. An Addis Single Rail Tramway, too. I expect ground conditions preclude traditional dual rail, but perhaps an Addis Tramway could do it, since there's no need to align rails. Just one rail to bear the weight and something vaguely road like for the balancing wheels. Might need quite narrow and long trains to keep the ground pressure low idk.