I am building a sort of space odyssey and I was wondering about something...

In a DnD game I used to DM, Starfinder I believe it was called, there was this asteroids belt and in it was some sort of space river. At the time I thought nothing of it, now I am curious...

So here are my two QUESTIONS :

Could a river actually form naturally around a planet or in an asteroids belt ? If not, could you create one and how would you create it ?

For my second question, you can have infinite resources and time. I would like science-based answers : no magic, or deity please (this is for both questions).

Finnaly for a bonus question : could this river sustain any form of life ?

Post-scriptum : Hope I was clear enough. I am sorry if there are any mistakes. English is not my first language. Cheers !

  • $\begingroup$ Liquids and vacuum are not compatible. Liquids cannot exist in a vacuum. (Not for long, in any case.) $\endgroup$
    – AlexP
    Sep 3, 2019 at 9:04
  • $\begingroup$ Related, if not duplicate worldbuilding.stackexchange.com/q/152747/30492 $\endgroup$
    – L.Dutch
    Sep 3, 2019 at 9:08
  • $\begingroup$ @L.Dutch it does look like my question, I had not read it. I will take some time at lunch to read through it. Thank you ! $\endgroup$
    – Dustman0
    Sep 3, 2019 at 9:11
  • $\begingroup$ @Dustman0 If only you have read the novel "The Fall of Hyperion", It explains the exact same thing, rivers flowing between asteroids, and in this aliens also use boats to travel between asteroids. I recommend you to read that, not the whole novel, just the small chapter that describes it. $\endgroup$
    – V.Aggarwal
    Sep 3, 2019 at 9:22
  • $\begingroup$ @V.Aggarwal I will gladly take a look later it seems interesting ! Thanks :) $\endgroup$
    – Dustman0
    Sep 3, 2019 at 9:46

1 Answer 1


No, for many reasons.

  1. The water would freeze - without atmospheric pressure water can only exist as ice or gas, it never exists as liquid.

  2. Even if you placed it in an atmosphere there is nothing to keep the water together, it would spread out.

  3. Even if you somehow kept it together surface tension would pull it into balls and droplets, not forming a stream.

  4. Even if you kept it in the shape of a stream it wouldn't flow, there is nothing to cause it to do so.

Basically you end up with pipes and pumps, which looks nothing like a stream.

The closest you could get would be a zero-g habitat with an enclosed atmosphere, a framework could be built and then water flow along that framework aided by pumps at each end and kept together by surface tension.

It would look cool, but flow slowly and look nothing like a river.

  • $\begingroup$ Thank you for your answer. Too bad for me that it doesn't work. If I don't get any answers I will validate yours. $\endgroup$
    – Dustman0
    Sep 3, 2019 at 9:05

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