# Living inside an asteroid? (sci-fi stuff) **URL:** \ **Category:** Factual Questions\ **Created:** [May 25, 2006, 11:03pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251 "2006-05-25T23:03:20Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![happywaffle](https://avatars.discourse-cdn.com/v4/letter/h/ee59a6/32.png) [@happywaffle](https://boards.straightdope.com/u/happywaffle)\ **Post date:** [May 25, 2006, 11:03pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/1 "2006-05-25T23:03:20Z")
Hey folks, Years ago I saw a science-fiction illustration of an an asteroid that had been hollowed out and set to spin, meaning people could live on the inside surface a la Ringworld. This seemed like a nifty way to transport a lot of folks on a long-distance journey, but I wonder how realistic it is. A few questions spring to mind about this scenario: (1) In the illustration, there was an artificial “sun” in one end of the enormous chamber. Would something like that possibly be an effective way to light and heat such a large room? Granted the closest and farthest ends of the asteroid would probably be inhospitable, but could a sizable temperate zone be devised using only a single light/heat source? I know they’ve managed to pull it off on Earth, but then our sun isn’t permanently in one side of the sky. (2) Could a large ecosystem exist in such a relatively small, closed system, without the benefit of weather patterns? This would (presumably) be like that Biosphere II experiment times a hundred. (3) Wouldn’t the forces of accelerating and decelerating cause everyone to lean forward or backward as they walked around the place? Isn’t this a problem with any potential spaceship that wants to incorporate some kind of gravity mechanism? I had an idea for a story based on this scenario but I’m really enjoying myself more just speculating on the logistics of such a ship. ---
**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\ **Post date:** [May 25, 2006, 11:33pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/2 "2006-05-25T23:33:25Z")
Try to find Gerard O’Neill’s book “The high frontier, human colonies in space” if you can, or research his ideas online. The general consensus seems to be that he underestimated the practical difficulties in constructing such habitats, and overestimated the political will of the time to set out on such a project, but the notion itself seems to be sound. His idea was more of artificial structures, made from asteroidal or lunar raw materials, but using an asteroid as the fundamental structure of a space habitat is a common variant. 1. Depends on the size and shape of the habitat, but it seems possible. I don’t see the advantage in putting it at one end instead of the center of the habitat, though. That makes the center your ‘tropic region’ and the ends your ‘poles.’ To even it out you might put two smaller light-heat sources closer to the ends. Most often, the light source is based on a system of gathering sunlight from the outside and reflecting it inside. 2. Depends on how natural an ecosystem you want. I think it would be practical for relatively controlled farming and raising chickens and other small livestock. You’d need to set up sprinkler systems for rain, maybe use fans to force air movements, etcetera, and watch that the soil stays healthy, that there are proper parasites to break down biomatter and keep it fertile, and that no malignant fungus starts to spread etcetera. 3. I think these effects wouldn’t be too noticeable… you’d get used to weighing slightly more as you moved towards or away from the spin. A greater problem, in very small habitats, might be the space sickness of your head weighing slightly less than your feet (because it’s further towards the center.) Hope this helps with your story and your speculation. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 26, 2006, 1:02am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/3 "2006-05-26T01:02:22Z")
> [@](#): > > 1. I think these effects wouldn’t be too noticeable… you’d get used to weighing slightly more as you moved towards or away from the spin. A greater problem, in very small habitats, might be the space sickness of your head weighing slightly less than your feet (because it’s further towards the center.) I think the OP meant that if you want to use this thing as a starship, you’ll need to give it a linear acceleration in addition to the rotation. Any practical starship drive will likely be continual-acceleration, which means one of two things. Either it’s a very low acceleration (say, 1/100 of a g), which is actually practical for a starship drive, in which case you just don’t worry about it (the “tilt” of the floor will be too small to worry about), or it’s a larger acceleration, in which case instead of making the inner surface a cylinder, you make it a stack of frustra of cones, with steps or elevators or whatever between them. So on any given cone, gravity would be more or less constant, and the floor would be more or less level. Of course, if you somehow have a strong enough propulsion system to maintain a constant 1 g, then you don’t bother spinning it at all, and just have “down” be towards the back of the ship. And you wouldn’t much want more than 1 g of propulsion, even if you had the tech for it, because there’s no way known to decrease the effective gravity. ---
**Author:** ![happywaffle](https://avatars.discourse-cdn.com/v4/letter/h/ee59a6/32.png) [@happywaffle](https://boards.straightdope.com/u/happywaffle)\ **Post date:** [May 29, 2006, 2:09am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/4 "2006-05-29T02:09:08Z")
Thanks for the responses. I guess a nice setup might be to have a light source at each end - greater and lesser - that pulsed opposite each other, to simulate day and night. Also sounds like such a spaceship might be able to be somewhat automated, y’think? I ask because my story idea involved folks living inside who forgot or didn’t know they were on a spaceship at all. Any other thoughts? ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [May 29, 2006, 5:34am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/5 "2006-05-29T05:34:44Z")
> [@happywaffle](#): > > Thanks for the responses. I guess a nice setup might be to have a light source at each end - greater and lesser - that pulsed opposite each other, to simulate day and night. The idea of having light coming from one end of the cylinder was basically a money/energy saving one, but it’s not applicable to a starship. The idea was to put a mirror at the end of the cylinder and reflect sunlight through a window into the interior. More optics (secondary mirrors or something) along the centerline of the ship would disperse the light somewhat evenly. Obviously, this won’t work for a ship in interstellar space, but will for a habitat in solar orbit. > [@](#): > > Also sounds like such a spaceship might be able to be somewhat automated, y’think? I ask because my story idea involved folks living inside who forgot or didn’t know they were on a spaceship at all. > > Any other thoughts? You do realize that the idea that the passengers/crew of a generation starship forgetting they are on a ship is not especially new, don’t you. I hope you come up with a new twist to this sf cliche. ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [May 29, 2006, 7:11am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/6 "2006-05-29T07:11:09Z")
An asteroid converted to an interstellar vessel is used in Russell’s _The Sparrow_, if you’d like another story where the practical considerations are discussed. That one uses a constant linear acceleration as described by **Chronos** rather than a spin. Also, it’s worth noting that planetary scientists argue about how many asteroids can be legitimately considered solid bodies of rock, versus gravitationally bound assemblages of smaller objects: clumps of gravel, basically. Reality is, some are one and some are the other, and there’s probably a range in between, but nobody knows for certain yet the relative proportions of the types. So it may or may not even be a realistic platform for construction. Read John Lewis’s _Mining the Sky_ for a detailed examination of asteroid makeup, according to our best information, and written for a lay audience. ---
**Author:** ![Pushkin](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@Pushkin](https://boards.straightdope.com/u/Pushkin)\ **Post date:** [May 29, 2006, 9:45am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/7 "2006-05-29T09:45:45Z")
> [@happywaffle](#): > > Also sounds like such a spaceship might be able to be somewhat automated, y’think? I ask because my story idea involved folks living inside who forgot or didn’t know they were on a spaceship at all. > > Any other thoughts? [Longest Star Trek episode title?](http://en.wikipedia.org/wiki/For_The_World_Is_Hollow_And_I_Have_Touched_The_Sky) 😉 How would a hollow asteroid stand up to impacts from other asteroids and meteors en route? ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [May 29, 2006, 1:27pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/8 "2006-05-29T13:27:54Z")
> [@happywaffle](#): > > Thanks for the responses. I guess a nice setup might be to have a light source at each end - greater and lesser - that pulsed opposite each other, to simulate day and night. > > Also sounds like such a spaceship might be able to be somewhat automated, y’think? I ask because my story idea involved folks living inside who forgot or didn’t know they were on a spaceship at all. > > Any other thoughts? [Sorry,](http://www.iol.ie/~carrollm/hh/n09-rev.htm) that’s been done as a novel too. Reviews on this page are mixed, I read it a while ago and found it OK without being exceptional. > [@pushkin](#): > > How would a hollow asteroid stand up to impacts from other asteroids and meteors en route? Very badly against anything of appreciable size, but the risk of such an impact actually happening would be small. ---
**Author:** ![happywaffle](https://avatars.discourse-cdn.com/v4/letter/h/ee59a6/32.png) [@happywaffle](https://boards.straightdope.com/u/happywaffle)\ **Post date:** [May 29, 2006, 1:51pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/9 "2006-05-29T13:51:50Z")
Sorry, I should have prefaced that with “I know the premise has been done before.” 🙂 Don’t worry, that’s not the twist of the story. I was just wondering how plausible it is. Thanks for the added recommendations. It wouldn’t even have to be an asteroid really - could (and probably would) be built from scratch. ---
**Author:** ![Jake](https://avatars.discourse-cdn.com/v4/letter/j/f475e1/32.png) [@Jake](https://boards.straightdope.com/u/Jake)\ **Post date:** [May 29, 2006, 8:00pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/10 "2006-05-29T20:00:49Z")
You might want to read “Rendezvous with Rama” by Arthur C. Clarke. Also Rama II by the same writer plus aurthor Gentry Lee. It covers a lot about what life would be like inside an giant asteroid or, in this case, something else! ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [May 29, 2006, 8:32pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/11 "2006-05-29T20:32:03Z")
[Generation Ships at Wiki](http://en.wikipedia.org/wiki/Generation_ship). > [@](#): > > The invention is credited to J. D. Bernal in his 1929 novel **The World, The Flesh, & The Devil**. A common theme is that inhabitants of a generation ship have forgotten they are on a ship at all, and believe their ship to be the entire universe. Famous examples of this include Brian Aldiss’s novel Non-stop, Robert A. Heinlein’s novella Orphans of the Sky, Gene Wolfe’s four-novel series Book of the Long Sun… ---
**Author:** ![Pushkin](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@Pushkin](https://boards.straightdope.com/u/Pushkin)\ **Post date:** [May 30, 2006, 9:39am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/12 "2006-05-30T09:39:02Z")
The Night’s Dawn trilogy from Peter Hamilton heavily features inhabited asteroids and giant living space stations (in between descriptions of horrible violence and planets fully of drunken Irishmen :rolleyes: ) ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [May 30, 2006, 10:54am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/13 "2006-05-30T10:54:15Z")
This was also the premise for the RPG _Metamorphosis Alpha_, where the campaign setting was a colossal multi-generation ship whose inhabitants had regressed to barbarism (and also mutated). Some of the earlier _Might & Magic_ games have settings like that too. ---
**Author:** ![Jake4](https://avatars.discourse-cdn.com/v4/letter/j/bc8723/32.png) [@Jake4](https://boards.straightdope.com/u/Jake4)\ **Post date:** [May 30, 2006, 1:46pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/14 "2006-05-30T13:46:15Z")
For an excellent story about humans living inside of Halley’s Comet (story is inside Solar System, no internal light source like you’re envisioning), read Heart of the Comet by David Brin & Gregory Benford. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [May 30, 2006, 3:15pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/15 "2006-05-30T15:15:41Z")
> [@Jake4](#): > > For an excellent story about humans living inside of Halley’s Comet (story is inside Solar System, no internal light source like you’re envisioning), read Heart of the Comet by David Brin & Gregory Benford. I enjoyed the book, but it was very different from what the OP is suggesting. The mission was to nudge the comet’s orbit to where it can be mined. They didn’t hollow out the comet, they just dug enough tunnels for a hundred or so people to live in. There was no artificial gravity (except a spinning excercise area, as I recall). Anyway, I really don’t see why you’d make a spaceship out of an asteroid. If you spun it to simulate gravity, it would break apart. You could reinforce it with metal, but you still have a lot of rock that’s not doing much other than slow down the spaceship. Basically, it’s akin to hollowing a mountain on earth to make an apartment building. It’s far more practical to mine the asteroid, purify the metal and use it to construct a spacecraft. ---
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [May 30, 2006, 3:41pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/16 "2006-05-30T15:41:47Z")
> [@chrisk](#): > > 1. Depends on how natural an ecosystem you want. I think it would be practical for relatively controlled farming and raising chickens and other small livestock. You’d need to set up sprinkler systems for rain, maybe use fans to force air movements, etcetera, and watch that the soil stays healthy, that there are proper parasites to break down biomatter and keep it fertile, and that no malignant fungus starts to spread etcetera. Well, it sounds good, but the practical difficulties of making this plan work mean that no one has yet figured this out. What a lot of people forget about the Biosphere 2 experiment is that it demonstrated that we really don’t have the technology or know-how to make a large-scale, isolated, self-sustaining ecosystem yet. I think eventually we’ll figure it out, given enough time. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 30, 2006, 8:52pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/17 "2006-05-30T20:52:23Z")
> [@](#): > > What a lot of people forget about the Biosphere 2 experiment is that it demonstrated that we really don’t have the technology or know-how to make a large-scale, isolated, self-sustaining ecosystem yet. Correction: What it demonstrated was that _the specific folks who made Biosphere 2_ didn’t have the needed know-how. The biggest problem with B2 was that the concrete hadn’t cured completely, and was still absorbing oxygen. You can get around this problem just by waiting a bit longer after you build the thing. And you could probably get away with a much simpler ecosystem than Biosphere 2, if you don’t mind having to do maintenance on it. ---
**Author:** ![Capa84](https://avatars.discourse-cdn.com/v4/letter/c/8edcca/32.png) [@Capa84](https://boards.straightdope.com/u/Capa84)\ **Post date:** [May 30, 2006, 9:56pm UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/18 "2006-05-30T21:56:22Z")
Of course it’s feasible. Everyone knows Earth was colonized by alien pioneers travelling in our hollowed out moon. ---
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [May 31, 2006, 12:12am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/19 "2006-05-31T00:12:56Z")
> [@Chronos](#): > > Correction: What it demonstrated was that _the specific folks who made Biosphere 2_ didn’t have the needed know-how. The biggest problem with B2 was that the concrete hadn’t cured completely, and was still absorbing oxygen. You can get around this problem just by waiting a bit longer after you build the thing. And you could probably get away with a much simpler ecosystem than Biosphere 2, if you don’t mind having to do maintenance on it. Fair enough, but I think Biosphere 2 is the only example of such an isolated large-scale ecosystem. I would also mention that we don’t have the technology or know-how to create working large-scale ecosystems even if they remain in contact with natural ecosystems. I’ve worked in restoration ecology, and my experience with wetlands restoration has not given me faith in human ability to create (as opposed to augement) functional ecosystems (A [cite](http://scholar.google.com/scholar?hl=en&lr=&q=cache:bdKIFt2E_8EJ:www.bol.ucla.edu/~linwoodp/ambrose.pdf+sudol+%22restoration+ecology%22) to let you know what I mean). We really don’t understand enough to put together all the parts in an open system, so I have serious doubts about our potential ability to succeed in a closed system. That’s not to say we haven’t had some limited success (I’d certainly like to think my own projects have had some success), but we’re definitely still learning baby steps when it comes to creating sustainable systems. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [May 31, 2006, 6:28am UTC](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251/20 "2006-05-31T06:28:24Z")
> [@happywaffle](#): > > Sorry, I should have prefaced that with “I know the premise has been done before.” 🙂 Don’t worry, that’s not the twist of the story. I was just wondering how plausible it is. The more I think about it, the more it seems that it’s virtually _required_ that a generation ship in sf have the inhabitants forget they are in a ship. I can’t think of any stories where such a ship has gone for more than a few generations without this happening. So maybe your twist should be that it _doesn’t_ happen 😃 [Next page](https://boards.straightdope.com/t/living-inside-an-asteroid-sci-fi-stuff/358251.md?page=2)