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Life in the asteroid belt

  1. Aug 29, 2015 #1
    So far i imagine things as following : instead of spinning up the whole rock, they have a spin station nearby, and build really big structures in microgravity, hangars for ships, factories etc.
    Due to lack of biosphere, it is common to reprocess dead bodies to food, fergitilizer.

    Questions : what can be the biggest working hazards there? In microgravity, they have hours before a mine collapses. Maybe overlook some minor damage caused by micrometeors, and a rocket blows up?
    Is there any suggestion, books that could help imagine everyday life there?
  2. jcsd
  3. Aug 29, 2015 #2


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    Same as on earth --- co-workers --- might actually be a break from the usual space operas.
  4. Aug 29, 2015 #3
    For example one is repairing a mining bot, other one gives it an instruction, so the repairer is flattened to a nearby wall?

    Well i also intend to mention crime, although a spin station is pretty easy to monitor, but probably it has multiple concentric levels.
  5. Aug 29, 2015 #4


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    James S. A. Corey's Leviathan Wakes has a lot of everyday life and the milieu out in the asteroid belt. Excellent read as well.

    It's the first book of the Expanse series.
  6. Aug 29, 2015 #5
    Read it. :) Had some inconsistencies, but it was a good book.
    What about the later books? I'm less confident with them, that they can repeat the end twist of the first.

    Although that book described really big cities, while i rather imagine small mining/factory towns on most rocks, and Ceres as a pirate heaven. (Well that place can have big cities with much entertainment.)
  7. Aug 29, 2015 #6
    You said about it some time ago, I accepted it first, but now I have some afterthoughts....


    Which elements they lack?

    Because, judging from meteorite composition, it is not so big effort to find one with abundance of elements that are used for life.

    Meteor showers are overrated, space is mostly just an empty space.
    1) human factor (stress, carelessness, sabotage)
    2) equipments... correct me if I'm wrong, but in your story such transport is still expensive (indentured servants / debt bondage). No gov to enforce health and safety regulations... and corporations who to maximize profit use equipment until it breaks down... oh yes... and to cut cost most of the equipment was presumably produced locally...
  8. Aug 29, 2015 #7
    Hmm, it looks like to me that micrometeor threat is real : http://sen.com/news/meteor-strike-on-iss-is-reminder-of-cosmic-hazard

    Well, mostly they land on metallic meteors, if i look at the iron meteorite column, they lack many things... although they land on C type meteors as well, to produce fuel.
    While the eat each other thing sounds really grim, and no need to take back bodies to Earth for bury, but i think about cutting it, or maybe explain, that they did it only on a few places, where many people had criminal records or something like that.

    Yes, both point 1 and 2 are fine. :)
  9. Aug 30, 2015 #8
    Hey, I'm not denying existence of meteorites, I'm just saying that threat, while looks cool for story purposes ("space specific" and "boom!"), has got too low probability to be significant. (yes, for each colonist killed by a meteorite, you should add dozen who connected incorrectly pipes for oxygen in their suit ;) ) Especially when to shield from radiation you used a thick layer of local material.

    Why not bury locally? Or incinerate and sent home ashes, while reuse the gasses? (that would be the best combination of dignity and economy ;) )

    I'm not saying that you can't recycle, my point is that in order to make such station economically feasible you have to mine many tons per hour per employee. Thus as byproduct you can get enough of elements for organic compounds.

    I found data for coal mining:

    10 tons per employee per hour for surface mining. And you go to space to boost productivity, right? 50 tons per employee per hour? So who would notice here even a 150 kg employee who died on hearth attack? ;)
  10. Aug 30, 2015 #9
    One more issue - transport cost.

    Its damn expensive to transport people there, so workers end up in debt bondage.

    Its very cheap to transport, so one can earn money by mining and exporting ores. (right now, price of iron ore 52$/ton, so to be competitive you should be able to transport it for less...)


    To make it realistic:
    -select a few, very rare elements, as the crucial and strategic one, for which it is worthy (iron would presumably be treated like water - useful but generally only produced for local consumption ;) )
    -make clear that there is one class of fast transport ships for passenger (like Concorde) and very cheap ore transport (like container ship)

    Wild, unbaked idea:
    Maybe just produce the desired metal (with outer later of something cheap), then build a huge glider shaped object out of it, put it on the right orbit (with tiny engine for minor corrections) and using rail gun accelerate it in direction of earth...

    Its cheap :D
  11. Aug 30, 2015 #10
    Hmm, the rail gun idea is good, but i think it doesnt really fit my setting. Not if they hadnt use the technology widely, but i assume ship speeds around 100km/s.
    The things launched from cannon cant decelerate from this speed without fusion power. From 10 km/s, they could possibly decelerate, but it would make them very easy to be intercepted with simple chem fuel missiles (frigates and privateers to intercept fusion ships are more expensive)

    Yes, they send rare materials to the planets from the asteroid mines, but they produce most equipment, spacecrafts etc locally.

    Ok, then i cut the man eating part, after all, it isnt a W40k underhive.

    I agree, that space hazards could be responsible for a small part of deaths and injuries compared to accidents caused by human errors, old equipment and crime.

    Well hybernation reduces the price of man transport, although there can be other issues. Leaving Earth's gravity well is not a negligable part of transport costs (i think only the construction expert megacorp has a space elevator, no fusion and nuclear propulsion in atmosphere). Provide training, food, water, oxygen, housing for workers. A good number of them could already face serious debts before start, that is why they leave Earth.

    I think transportation is rather cheap than expensive, still it looks logical to me, that once they taken someone there, they dont want that person to simply return to Earth after a few months, maybe he should pay not just the transport, but all other lifesupport costs in advance (and take his account to minus).
    Launch windows still apply more or less, even a fusion ship wont go around the Sun to reach its goal.
  12. Aug 30, 2015 #11
    So maybe send a swarm of tiny gliders that weight 1 ton each? And accept that 10% of them would be intercepted?

    I see here a problem. Let's say that hull of a ship and engine weight 200 tones. You can either load missiles/gun that weight 50 tones or 800 tones of ore. If you assume that full cargo ship cruise with 100 km/s, then it would be pursuit by the military one with 400 km/s. No friction in space, just delta-V, so concerning speed there would be no natural limit. It heavily favour the guy without heavy cargo but with a light gun.

    And as there is no stealth in space, while chased by someone with 400 km/s, the guy with 100 km/s would have not much better chances than cheap cargo transport with 20 km/s.

    (the only limit for manned ship is acceleration)

    Maybe idea that crude stuff locally, complicated electronics - has to be imported?

    You may actually make your characters think what happens to the gasses after cremation in closed system... ;)

    OK. Anyway, the space exploration on mass scale started long time ago, to justify huge quantities of old equipment? (just in case - don't worry - there is also new, not fully tested equipment ;) )

    If it is used for invasion, that means that it is simple and don't affect organism performance. Too good.

    Careful. If space travel is cheap, then many simpler things should be damn cheap. Which makes the whole setting less dystopian. You know, proles who can easily afford to go on round the world trip spoil the whole sinister setting ;)

    Launch window?
    "The minimum distance from the Earth to Mars is about 54.6 million kilometers. The farthest apart they can be is about 401 million km."
    Dividing it by 100 km/s you get 6.3 days to 46 days. (yes, very rough approximation) Not tempting for manned travel, but cargo transport can be also sent outside the window, with same delta-V, so it would be presumably a better business, than hold the ship in hangar. (assuming that no-one hunts for your ships...)
  13. Aug 31, 2015 #12
    My calculations are different. Exhaust velocity around 100km/s. Kiloton to 100km/s mass ratio e, around 3 kiloton.
    250 ton to 400 mass ratio e on 4, more than 10 kiloton.
    I think about the space cannon idea, send a fusion ship to intercept is way more expensive, the cargo ship can deliver things way more fast, on the other hand, if they send small cargo units, even if the majority of them is intercepted, is still more than a ship that dont arrive.

    Well, i think they travel space for 100 years at least, yes a single asteroid can produce many things, but not everything.

    In case of the far away planets, during that months of travel, the ship could make multiple voyages between different types of asteroids. Also going around the Sun is still a dont launch window IMHO.

    At this point, I wrote that even garbage heap inhabitants dont starve.

    If i want to think seriously about the invasion of Mars (and piracy), transport needs to be cheap, also hibernation is required to decrease advantages of robotic ships and troops.
  14. Sep 2, 2015 #13
    Ok, i think it could be an alternative to ships (mostly used by construction expert megacorp and moon bankers, my scientist hero could have the exam work of perfecting the mass drivers, so they dont require so much maintenance. Yes the ships expends much more energy, but not in a fraction second.)
  15. Sep 4, 2015 #14
    Explain it please one more time, in plain words.

    OK, clear.

    Starts having interesting consequences ("space not sea"). So are you going to make a spreadsheet calculation with distance of all important bodies in motion. And calculate from it how space trading / invasion dates.

    At this time proles go to Antarctic for holidays and complain that got ripped off by evil meg ;)

    Dunno. In Frank Herbert Dune transport was expensive, but invasions was still possible. I see one serious advantage of expensive / complicated transport - defender's advantage. It doesn't matter whether you have 100 robotic armies on Mercury, if you can transport in one go only one army in one go. Thus the biological army would have one serious advantage - it was produced locally, thus no shipment fee.

    Actually expensive transport explains why there is still no clear winner.
  16. Sep 4, 2015 #15
    Part one, due to rocket equation (if my calcs are correct) higher speeds requires exponentially more fuel, while a bigger base mass only boost fuel requirements linear.
    Part two : so the fusion ship has the following merits
    - the advantage of speed, multiple volyages, till mass driver launched cargo arrives
    - it simply outruns a chem-fuel missile, intercept it isnt that cheap

    Mass driver launch has the following issues
    - cheap, (even military grade coilguns are widely used in my world with 100km/s at 5m)
    - redundancy, if 9 out of 10 lost, the tenth that arrives is still more than a ship that turns to space debris (well, i'll write one of my character want to fish out the valuables from the wrecks of a cargo ship after the enemy attacks the convoy. But that is a rather special case, since he can take the same course in a not so long time.)
    - on the other i think mass driver launch isnt THAT cheap. Boost lots of cargo to 100km/s more energy than boost a container to 10km/s. But a ship has days for acceleration, the mass driver has to expend the necessary energy in less than a second (unless they want to build it kms long), so i think the mass driver requires quite an amount of maintenance

    Yes i find that part interesting.

    Planetary defence can launch swarms of missiles, defence lasers have much better waste heat treatment than the fleet, attacking a celestial is still very expensive.

    They have similar amounts of free days as in Japan. Possibly chinese like working conditions.
    But yes, if they have the free day, they can fill their facebook page with pictures from all around the globe. :)
    Last edited: Sep 4, 2015
  17. Feb 17, 2016 #16
    I wonder, what can be the important jobs, professions, qualifications there? (Based on mines, oil drill platforms and ISS)

    (For my story i speculate, that due to unemployment on Earth, greatly reduced travel costs - hybernation, laser assisted rockets to take off from Earth, slight transhumanism, there wont be maintenance bots maintained by robots controlled by an AI)
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