Would building a crescent shaped habitat work if you didn't want to go all the way?

Edit: I'm asking if this would be enough to provide artificial gravity, sorry not not being clear about it.

  • $\begingroup$ "work" how exactly? $\endgroup$ Mar 30, 2021 at 0:14
  • $\begingroup$ You dig into the asteroid far enough to cover the outer surface of the habitat (which would be more of a semi-circle or a quarter than a crescent shape) with 3d printed regolith. Taking advantage of the asteroid's spin without it being a full circle. $\endgroup$
    – billy
    Mar 30, 2021 at 0:21
  • $\begingroup$ Are you talking about artificial gravity? $\endgroup$ Mar 30, 2021 at 0:24
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    $\begingroup$ If you use the full radius (262 km) and the rotation rate of once per 5.34 hours I get .003 g's at the equator, so probably not worth bothering with. Please check my math though. $\endgroup$ Mar 30, 2021 at 0:46
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    $\begingroup$ @OrganicMarble it's worse, since the surface gravity is 0.025 g in the other direction. You'd just be picking the part of the asteroid where the effective surface gravity is the lowest. The poles would be better because the two vectors wouldn't be opposed, but the amount it'd add wouldn't be worth thinking about. $\endgroup$ Mar 30, 2021 at 1:53

1 Answer 1


Like most large asteroids, Vesta is held together by its own gravity, even if it's not held strongly enough to put it into hydrostatic equilibrium. As a result, if Vesta spun fast enough that it could provide a spin gravity at any point in its interior higher than its surface gravity, the centripetal acceleration provided by its own gravity would not be enough to hold it together, and the asteroid would come apart.

In other words, you'll get higher gravity by putting your habitat on the surface.

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    $\begingroup$ This is the problem with spinning up most asteroids to give them artificial gravity. People assume an asteroid is a single large rock, while in reality they tend to have many, many pieces to them, held together by gravity, just like virtually any landscape on Earth. Spin up the asteroid enough for centripetal acceleration to act as artificial gravity, and you've probably spun the asteroid apart $\endgroup$ Mar 30, 2021 at 1:45
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    $\begingroup$ Yeah, if you want an asteroid to be involved in an artificial/simulated gravity scheme, you're better off stuffing a rubble pile in a big bag and using it as a counterweight. $\endgroup$ Mar 30, 2021 at 1:55
  • $\begingroup$ What if - stay with me here - you anchored a tether deep inside Vesta somehow (I don't know, with a grapple structure like a giant drywall anchor or by melting a quantity of deep rock or something) and then had that tether attached to a living structure a distance away from Vesta? If you got the distance right, could you use Vesta as a sort of pre-made counterweight? $\endgroup$ Mar 31, 2021 at 16:22
  • $\begingroup$ @SpaceLawyer You'd be essentially building a space elevator, one significantly longer than the synchronous orbit radius for Vesta, If you have enough traffic for need of one over Vesta, great. Otherwise, most civilizations would probably spend less and just build rotating stations in orbit. $\endgroup$
    – notovny
    Mar 31, 2021 at 17:12

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