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In my world Deimos is a thriving port city in which numerous people live. The most inhabited and built up area is the Central Hub, a large cylinder about a football field (either kind) in diameter, which extends about a third of the way into the moon. Running along the center of the cylinder is a "beam" which contains the main lighting and transit system, at various points there are supporting girders that lead down to the "floor" that provide access from the tram to the "floor." Since Deimos's gravity is 0.003 m/s, anyone within would be in almost freefall. As such I have been unable to think of ANY structures and building arrangements that could provide access to the light from the center, take advantage of the room and microgravity and be easily built.
So does anyone have any ideas, links, reports or such that could help or provide an answer?

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closed as unclear what you're asking by Mołot, Shadowzee, JohnWDailey, Ryan_L, John Oct 24 '18 at 1:54

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ I'm voting to close this question as Unclear. You appear to be asking for idea generation or resource links and in my opinion have done a poor job explaining your world. To Nitpick a little, gravity is in m/s^2. If your gravity is 0.003m/s^2, then freefall would be the same as floating. They are going down so slowly calling it freefall is a bit absurd. The building you've described is what I can only picture as a giant tower with a elevator and light system placed in the center. Anyone could reach it by just floating across the gap since gravity is so low. $\endgroup$ – Shadowzee Oct 23 '18 at 22:42
  • $\begingroup$ Deimos is one of Mars's moons, and itself is an asteroid. The structure I am talking about is part of the city built on Deimos. The biggest "neighborhood" is the Central Hub, which is a giant cylinder. Im asking about what structures might be built along the walls and upward without filling the whole space. Thus providing some level of roominess. $\endgroup$ – The Imperial Oct 23 '18 at 23:16
  • $\begingroup$ You should add the part about the structures to your question. It makes more sense if you explain that the structures need to be build along the wall and extend towards the center (without actually reaching the centre). I was imagining giant circular cylinder with floors and some elevators in the middle. $\endgroup$ – Shadowzee Oct 24 '18 at 0:46
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If I understand correctly you mean the "floor" to be the interior surface of the cylinder? If this is a true freefall (yes, that is the correct term) environment the concept of "floor" doesn't really apply. Add to this that your desired layout essentially creates a bunch of pie-shaped rooms that are 50 yards tall (I chose American football) with walls that slope together as they rise. Weird and probably not space-efficient.

However, the biggest issue here is that 0.003m/s^2 is not zero. If someone slept for 8 hours under 0.003m/s^2 acceleration without being strapped in and with unlimited room, they would be moving ~86m/s (~200 mph) when they woke up. A better example: if someone started at the top (edge near surface of Deimos) of your structure and let themselves fall, they would find themselves at the bottom only 20 minutes later moving at ~3.6m/s (~8mph). Not so scary, but way past noticeable.

So I would contend that the very slight gravitational acceleration matters, and your "floors" should probably be regular circular cross sections perpendicular to the main "beam". Essentially if humans are going to be in rooms where everything is always slightly accelerated in one direction, it would be most comfortable to have that direction be "down." This would make your building much like a 1.3 mile tall skyscraper that extends into the moon, and I'm sure you could take real-world examples on how to subdivide that.

I should also note that 0.003m/s^2 is probably an average surface gravity. Deimos is too small for its gravity to pull it into a totally spherical shape, and I would wager the surface gravity varies place to place. Also, If your structure extends a third of the way into the moon, the gravitational acceleration will decrease as you go down. Specifically, if we make a (rough) assumption of a spherical Deimos, the gravitational acceleration will decrease linearly with decreasing radius. That is, at 2/3 of the distance from the center ("1/3 of the way in to the moon"), gravity will be 2/3 of surface gravity: 0.002m/s^2. Happy to show the math on these points if you're interested.

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