Imagine this:

All celestial bodies significantly smaller than a planet within our solar system (asteroids, debris etc.) are moved into an orbit around earth. The method of achieving this is not my concern.

  • Is this possible for comets? Will they 'survive' earth orbit?
  • What are the implications on earth?
  • What range to earth would be ideal for safety, minimal impact on earth and on the other hand small enough for convinient extraction / mining?
  • Do we need to limit the number of celestial bodies to avoid gravitational effects (floods an so on)?
  • Could this ever be stable, i.e. all bodies moving within stable curves?

I know there is a somewhat similar question, but I find it different enough to ask this question.

As always, thanks for your time!

  • $\begingroup$ Are you asking about Roche limit? $\endgroup$
    – user6760
    Aug 16 '15 at 3:07
  • $\begingroup$ I just looked this up, seems to be part of my question, yes :) $\endgroup$
    – user6415
    Aug 16 '15 at 10:55
  • $\begingroup$ See also en.wikipedia.org/wiki/Lagrangian_point $\endgroup$
    – Keith
    Aug 17 '15 at 6:26
  • $\begingroup$ Thanks, this is quite interesting, just a bit 'too deep for my usual demands' :) $\endgroup$
    – user6415
    Aug 17 '15 at 9:38
  • $\begingroup$ "What are the implications on earth" strikes me as far too broad. Risk of impactors? Seismology? Technology required to safeguard population? Population shifts to asteroid-bases? Societal breakdown as the populace believes the end is ngh? Minerals access? $\endgroup$
    – nitsua60
    Mar 19 '16 at 5:28

This would be a big problem.

The entire asteroid belt is approximately 4% the mass of the moon (this includes the dwarf planet Ceres). All the trojan asteroids add up to about one-fifth of the mass of the asteroid belt. The Kuiper belt is next, its total mass is estimated to range between 1/25th and 1/10th the mass of the Earth. So far, no problem.

Then there is the Oort cloud.

The Oort cloud is at the edges of our solar system and it is huge, literally astronomically huge. It also turns out it's fairly massive. The exact mass of the Oort cloud isn't known, but estimates put it between four and eighty times the mass of the Earth.

Anyone who adds eighty Earth's worth of mass into orbit around the Earth is not going to have a good time. There is a perspective shift here, and it might make more sense to say the Earth is orbiting the debris. A lot of the effects are going to depend on the balancing of that mass in orbit around the Earth, needless to say, it's not going to be a simple task. Such a thing could be stable, but only for a short period of time, it's far too much mass to keep track of and maintain. It's also far more material than could conceivably be needed for mining, but we passed that threshold when we brought the entire asteroid belt (with a dwarf planet) in for mining.

  • $\begingroup$ Would it work when you exclude the Oort cloud? $\endgroup$
    – user6415
    Aug 16 '15 at 10:51
  • $\begingroup$ @openend Possibly, no oort cloud and no moons and it might not destroy the Earth if you're exceedingly careful. $\endgroup$
    – Samuel
    Aug 16 '15 at 15:26

Basically, everybody dies

Moving that many bodies into near earth orbit is going to have serious implications because none of those orbits are stable and collisions will be frequent and spectacular.

For a visualization of this process of decaying orbits, check out this video made in Universe Sandbox 2. Something is going to hit earth and chances are, it will be big. Anything with orbital velocity above 10km in size is going to be a huge huge problem. Maybe not enough to boil the oceans but definitely an extinction level event.

Burning Moons are terrifying cool!

  • $\begingroup$ I enjoyed the video! Thanks a lot, the impressions will help a lot while envisioning this scenario. $\endgroup$
    – user6415
    Aug 17 '15 at 9:59
  • $\begingroup$ @openend if you are so inclined, the game that video was made with is available now so you would be able to make up and test your own scenarios. $\endgroup$
    – Green
    Aug 17 '15 at 11:22
  • $\begingroup$ That video's pretty funny. $\endgroup$ Aug 17 '15 at 14:12