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moon, is enough prerequisite for colonization. Better any atmosphere than none!
The energy sourse for this is there: using electrodinamical tethers attached to the cis- and trans-neptunian points of the moon`s surface, passing though the triton-neptune L1 and L2 points and extended as much further as the structural integrity strenght of the tether allows, will turn the orbiting moon in a kinda dynamo... The electric currant gained from the orbital motion of Triton+cables through the big magnetosphere of the mother-planet on account of lowering incrementaly the moon`s orbit should be sufficient to have there on disposal the vast amount of heat necesarry to vaporize trillions of tonnes of N2 to form dense , several bars of atmosphere at 70-80 K ambient temperature. It indeed could be targeted the N2 triple point in order the same way as the water on Earth, the N2 to exist in solid/liquid/gas state.
Extremelly cold, but in matter of phase states of the surrounding matter, quite earth-like and technologically usefull environment! Gaseous 'air', seas and oceans of very water-like LN2, nitrogen ices where it is still cold enough. Technologically "naturally" even more benign for techs like superconductivity for example. The low gravity will allow really huge buildings-cities ( arcoilogies) to be deployed there. At 7-8% gees kilometric size "IGLOOS" can be constructed containing billions of cubic metters of terraformed envronment, powered by the orbital mechanics eletrodynamic system for at least 100 000 000 years ( untill the deorbbited moon is shattered to pieces by the tidal forces of Neptune), independent from the sun or sourses of any "fuel"... or longer if the celestial mechanics of the entire Neptune lunar system is used...
The same titan-forming could be done on every sufficiently large Kuiperoid via soletas to concentrate enough of the scarse solar radiation on that distances to provide nitrogen evaporation.
BTW, what are the solvent properties of the LN2? I think it is in principle possible to be composed a life-like eco-technology based on LN2 solvent "bio"chermistry... Accoirding to Steven Benner we should take into serious account the possibility ofgv non-water-solvent based life, as the case of liquid amonia and methane on Titan, dihydrogen/helium supercriticals in the gas giants, and other much more plentifull solvents present in the Solar system. Even if such life, how it seems is much unlikely to occur/evolve, that doesn`t means that it could not be created. Envision it as another type of 'wet'ware nanotechnology, as the natural bio-nanotech based on water organic solutions on Earth.
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Splendid comment of such idea about warming distant/icy mini-worlds up to temperatures usefull for beseline humans collonisation ( from http://www.orionsarm.com]www.orionsarm.com forum):
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Hi OA
The suggestion for "warming up" Triton is interesting. Some early radio
observations of Titan in the 1970s suggested a surface at ~ 200 K, leading
to some radical models, 21 bar atmospheres of nitrogen most famously.
Titan's current 95 K @ 1.6 bar is on a continuum with such models, unlike
the opposing model of just 87 K and Mars-thin methane-only atmospheres.
Titan is currently too warm for nitrogen to condense - all the way to the
top of the atmosphere - and multi-bar atmospheres over nitrogen seas are
unstable with respect to nitrogen's phase diagram. The current low methane
atmosphere is also only meta-stable as a mere 10% insolation rise would
cause all the exposed liquid to vaporise and create a ~ 5 bar atmosphere and
about ~ 140-150 K surface temperature. By about ~ 2 Gyr from now Titan will
be "hot" enough for ammonia seas to melt out of the ice at ~ 178 K.
Ammonia/water eutectics will be possible at higher temperatures.
Back to Triton, in his "Manifold: Space" Stephen Baxter bombed Triton with
Nereid to give it a geochemical cycle to make colonisation easier. Nereid
would crash into Triton from the opposite direction to its retrograde orbit
at 10.4 km/s releasing enough energy to melt the upper ~ 100 km of ices...
but there are complications. Triton has a relatively high density of ~
2.065, so if it was just a mix of water ice (<rho> ~ 0.94) and rock (<rho>
~ 3.5) it would have a huge rocky core and a thin icy shell. However it also
has carbon dioxide ice and that's a relatively high density of ~ 1.7 at
Triton temperatures. Also there's bound to be large amounts of methane
clathrate, so I wonder if the result of warming wouldn't be a dense blanket
of CO2, probably condensing into liquid at the bottom of the atmosphere. A
sufficiently opaque atmosphere could retain impact heat for ~ 1000s of years
keeping the place in a ferment in the 11th millennium. Also the ~ 170 km
radius of Nereid means it could penerate the ice and heat the rocky core
directly, storing some heat for a slow trickle over immense time spans.
According to Javier Ruiz (Icarus, vol.166 pp. 436) Triton's very young
reworked surface is a strong indicator that it has a relatively shallow
NH3/H2O ocean, perhaps a mere 20 km below the ice.
http://adsabs.harvard.edu/cgi-bin/nph-b … bin....p;\
db_key=AST
Also Triton was probably captured into Neptune orbit via a collision then
tidally braked down to its current orbit over 1 Gyr, releasing immense
amounts of energy in the process (Goldreich et al, Science v. 245, pp 500.)
This almost certainly kept the atmosphere inflated to the dense, warm
multi-bar level and perhaps allowed life to get a head start.
Hence blasting off into atmosphere the outer layers might reveal a warmer
place than compatible with liquid nitrogen.
Adam
----- Original Message -----
From: "vorakarov" <karov@l...>
To: <orions_arm@yahoogroups.com>
Sent: Monday, January 17, 2005 12:33 AM
Subject: [orions_arm] Re: [AOL/News] Huygens on Titan
[snip]
>
> Triton in this respect could be titan-formed easily using
> electrodynamical tethers to harvest it celestial mechanicval orbital
> energy to vaporize several bars of N2 in thick envelope... If the
> pressure/temp fits the triple point of the N2, than quite earth-like
> in phase states world would appear -- with gaseous air, water-like
> LN2 oceans, ice-cups of solid N2 where the temperature is low enough.
> Imagine life-like based on LN2 as solvent!
>
>
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More datails from the same guy "Adam" from Crowlspace archive:
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"Bombing Triton
Stephen Baxter in his "Manifold: Space" novel has a character cause the collision of two of Neptune's moons, Nereid and Triton, to give Triton an energy boost, making it more habitable for Aboriginal refugees from Earth. So I ask: what would such planetary engineering require?
Name Semimajor axis (10^3 km) (Neptunian Radii) Orbital Period (Days) Inclination (degrees) Eccentricity Orbital Velocity
Triton (NI) 354.76 14.328 5.876854R 157.345 0.000016 4.39 km/s
Nereid (NII) 5,513.4 222.67 360.13619 7.23 0.7512 1.11 km/s
As you can see Triton is about as close to Neptune as Earth's Moon is to Earth, but about 4 times quicker. Nereid is a long, long way out. Such an orbit would be unstable around the Earth and it would become a Near Earth Asteroid.
An important feature of Nereid's orbit is its high eccentricity - it actually orbits between 1.3717 million km and 9.655 million km, reaching 2.953 km/s at the low point and a mere 0.4195 km/s at the high point. Quite a roller-coaster ride. Also the eccentricity means that Nereid spends ~ 74% of its orbital period higher than the average distance, and a mere 26% of the time closer to Neptune.
To crash Nereid into Triton requires lowering the low-point (the periapsis) by losing velocity at the high point (the apoapsis.) To lower Nereid into Triton's orbital path - conveniently opposite to Nereid's - it needs to shed ~ 196 m/s. How much would that require in time and rocket thrust?
Firstly, Nereid is 340 km across and masses ~ 30 quadrillion tons. Deccelerating it by 196 m/s takes ~ 6x10^21 Newtons of force in total. That's a lot of force! Baxter deploys huge ion engines to do the job, but they're probably the worst for the job. Rockets are characterised by exhaust velocity and their jet-power. Ion drives generally have a high exhaust velocity but a low jet power - maybe 100 megawatt for advanced ones. Nuclear Thermal Rockets however have a medium exhaust velocity and a very high jet power - up to terawatts of power for very large NTRs.
A high-end NTR can get 10,000 m/s jet velocity, hence a velocity change of 200 m/s will need ~ 1/50th of the total mass to be moved, expelled as propellant. In Nereid's case that's ~ 600 teratons of mass - probably a mix of methane, ammonia and water ices extracted from Nereid directly. Spread over several years of thrusting (~ 60 million seconds), that's 10 million tons/second, and a 500,000 terawatt jet-power. An incredible figure. Baxter, we might say, glossed over the difficulties involved.
Alternatively we might deploy a fusion engine of some sort - probably a pulse drive - with a very high exhaust velocity and jet power. For the same thrust-time a fusion drive with ~ 10,000,000 m/s exhaust velocity has a power of 500 exawatts - 1000 times the previous power-levels. Insane amounts of energy. Like exploding 120,000 megaton bombs every second...
Assuming we do bomb Triton with Nereid, what will it be like? The impact speed is ~ 10.4 km/s, and the total energy released is ~ 1.6x10^27 Joules... or about 400 billion megatons TNT equivalent (FYI... TNT packs about 4.2 megajoules/kilogram, hence a megaton is ~ billion times that, some 4.2 petajoules.) Assuming Triton's ice-crust is at ~ 38 K about ~ 700 km of crust would melt all over the moon. However that simplifies far too much. If Triton were just ice and rock then it's about 56% rock, collected in the core, and the ice is just ~ 240 km thick. Nereid's remains would probably penetrate the ice and heat-up the core via direct collision.
However there are good chemical arguments that suggest Triton has a lot of carbon dioxide and methane ice, plus an outer layer of nitrogen/ammonia ices. The resulting ferment would leave Triton with a much thicker atmosphere for a long, long time.
Posted at 1:34 am by Adam
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You see the bombing with Nereid version of warming Triton, needs lots of energy if used huge rocket method for delivery of the impactor and sufficent amount of propelant ( i.e. fraction of the Nereid mass) to be rocketed.
Other way to reorbit Nereid into collision course with Triton is to use the energy confined in other bodies in the Neptune system via PaulBirchean planet shifter mass-stream technology utilizing the natural planetary dynamo through electrodynamic tethers.
The other way is to redirect one or several near TNOs with lesser delta-V budget, than the Nereid version, to merge with Triton and to reinject it with heat.
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