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I'm sure you already know, The Moon Is a Harsh Mistress by Heinlein is such a great book that deals with exactly this.

Kim_Bruning 5y ago
Also in The Expanse (possible spoilers?) it takes the Belters a surprisingly long time to realize they're holding the ultimate high ground in this respect.
- omegalulw 5y ago
  I mean not really? That scene [SPOILERS AHEAD] always seemed like a plot hole to me - you need massive Delta V to change trajectories of objects in space to hurl them towards earth and you need them to be massive to not burn up in the atmosphere. That takes a loooot of juice. It's much easier to use the "Rods from God" idea - that is more precise and minimizes collateral damage.
  - Kim_Bruning 5y ago
    There's a surprising number of near-earth objects that might (almost) hit earth anyway, that really only need a nudge. And if you're not in a huge hurry, you can use high ISP electric powered rockets. And since you're in the inner solar system, solar power isn't very expensive either. IRL you can use brain-power to avoid using muscle-power! On the other hand, in-universe, they've got brute-force Epstein drives. For them this is Tuesday.
    - omegalulw 5y ago
      But if you want to "nudge" an otherwise near miss asteroid you gotta wait till however long till it comes around, which can be 1000+ years? From https://www.britannica.com/science/Earth-impact-hazard/Frequency-of-impacts https://www.britannica.com/science/Earth-impact-hazard/Frequ...: > Because there are far fewer large NEOs and long-period comets in space than smaller ones, the chances of a collision decrease rapidly with increasing size. The impact-hazard community—primarily scientists with an interest in the issue—has defined a global catastrophe to be an impact that leads to the death of one-fourth or more of the world’s population. An impact by a 1-km- (0.6-mile-) diameter NEO, the smallest believed capable of causing such a catastrophe, is estimated to occur about once per 100,000 years on average, based on the assumed population in space of such objects. On the other hand, an impact by a 100-metre (328-foot) NEO, the smallest believed capable of causing regional devastation, is estimated to occur about once every 1,000 years on average.
      - omegalulw 5y ago
        I guess that link will underestimate the number of near misses but looking at https://en.m.wikipedia.org/wiki/List_of_asteroid_close_approaches_to_Earth https://en.m.wikipedia.org/wiki/List_of_asteroid_close_appro... the number of 100m+ objects isn't that common?
        Kim_Bruning 5y ago
        Well, look at it this way: https://www.youtube.com/watch?v=BKKg4lZ_o-Y https://www.youtube.com/watch?v=BKKg4lZ_o-Y [Asteroid Discovery - 1970-2015 - 8K resolution] Take your pick! And remember one doesn't need a tidy Hohman transfer. Rather the opposite in fact. The nastier the intersect angle the better. (Hopefully we don't end up on some watchlist :-P )
  - LargoLasskhyfv 5y ago
    No more plot hole than the Epstein drive. That's the handwavium there. Depending on the nature of the Asteroid, it wouldn't have to be larger than anything between a SUV or bus. Which even small private yachts could push on course. INSTABANG!1!!

Also in The Expanse (possible spoilers?) it takes the Belters a surprisingly long time to realize they're holding the ultimate high ground in this respect.

omegalulw 5y ago
I mean not really? That scene [SPOILERS AHEAD] always seemed like a plot hole to me - you need massive Delta V to change trajectories of objects in space to hurl them towards earth and you need them to be massive to not burn up in the atmosphere. That takes a loooot of juice. It's much easier to use the "Rods from God" idea - that is more precise and minimizes collateral damage.
- Kim_Bruning 5y ago
  There's a surprising number of near-earth objects that might (almost) hit earth anyway, that really only need a nudge. And if you're not in a huge hurry, you can use high ISP electric powered rockets. And since you're in the inner solar system, solar power isn't very expensive either. IRL you can use brain-power to avoid using muscle-power! On the other hand, in-universe, they've got brute-force Epstein drives. For them this is Tuesday.
  - omegalulw 5y ago
    But if you want to "nudge" an otherwise near miss asteroid you gotta wait till however long till it comes around, which can be 1000+ years? From https://www.britannica.com/science/Earth-impact-hazard/Frequency-of-impacts https://www.britannica.com/science/Earth-impact-hazard/Frequ...: > Because there are far fewer large NEOs and long-period comets in space than smaller ones, the chances of a collision decrease rapidly with increasing size. The impact-hazard community—primarily scientists with an interest in the issue—has defined a global catastrophe to be an impact that leads to the death of one-fourth or more of the world’s population. An impact by a 1-km- (0.6-mile-) diameter NEO, the smallest believed capable of causing such a catastrophe, is estimated to occur about once per 100,000 years on average, based on the assumed population in space of such objects. On the other hand, an impact by a 100-metre (328-foot) NEO, the smallest believed capable of causing regional devastation, is estimated to occur about once every 1,000 years on average.
    - omegalulw 5y ago
      I guess that link will underestimate the number of near misses but looking at https://en.m.wikipedia.org/wiki/List_of_asteroid_close_approaches_to_Earth https://en.m.wikipedia.org/wiki/List_of_asteroid_close_appro... the number of 100m+ objects isn't that common?
      - Kim_Bruning 5y ago
        Well, look at it this way: https://www.youtube.com/watch?v=BKKg4lZ_o-Y https://www.youtube.com/watch?v=BKKg4lZ_o-Y [Asteroid Discovery - 1970-2015 - 8K resolution] Take your pick! And remember one doesn't need a tidy Hohman transfer. Rather the opposite in fact. The nastier the intersect angle the better. (Hopefully we don't end up on some watchlist :-P )
- LargoLasskhyfv 5y ago
  No more plot hole than the Epstein drive. That's the handwavium there. Depending on the nature of the Asteroid, it wouldn't have to be larger than anything between a SUV or bus. Which even small private yachts could push on course. INSTABANG!1!!