From: northerntiger@outlook.com   
      
   On Monday, April 16, 2018 at 5:19:52 AM UTC-4, eripe wrote:   
   > On Friday, April 13, 2018 at 11:25:22 AM UTC+7, johnny1...@gmail.com wrote:   
   > > In another thread, the relative choice of use of atomic bombs vs other   
   means as weapons by a space-going society against a target world came up.    
   Assuming you have access to FTL travel so you can travel from star to star in   
   reasonable times, that is.   
   > >    
   > > So let's break it down.  A spacecraft that can come close to a target   
   world with a hold full of nuclear weapons and delivery systems can, in theory,   
   rain those bombs onto targets across the planet, modulo defenses in place.  In   
   principle, a    
   relatively small vessel can carry enough fission or fusion devices to wipe out   
   a huge number of cities or facilities.   
   > >    
   > > (How many nuclear bombs and delivery systems could have been packed in the   
   Shuttle Orbiter cargo bay, for ex?)   
   > >    
   > > The positive side from an attacker POV is that nukes are compact,   
   relatively cheap, safe to store if you know what you're doing, and fast.  The   
   big negative may or may not be radioactive contamination, depending on whether   
   the attacker actually cares    
   about that or not.   
   > >    
   > > Alternatives:   
   > >    
   > > 1. Asteroid impact.  It's true that a space-going attacker might well be   
   able to pick out a nice rock and steer it into a collision orbit.  Such an   
   attack can be devastatingly potent when it hits, as Chicxulub mutely   
   demonstrates.   
   > >    
   > > Upside - Radioactive contamination is not an issue (if you care about   
   that).   
   > >    
   > > Downsides - Slow.  It takes time, maybe a long time, for the rock to get   
   where it's going, unless there just so happens to be one in just the right   
   place for a nudge to do the job, which is improbable.  It might be months or   
   _years_ before your rock    
   does the nasty to the target.  Such a long period might be annoying, and it   
   might give the target time to do something about it, and you.   
   > > Also, even if there's no radiation, the planet is going to be messed up   
   pretty thoroughly if you use a big rock, so there's still issues in using it   
   afterward, if you intend that.   
   > >    
   > > If you've got enough delta-V, of course, you can get your rock there a lot   
   faster, but past a certain point, if you can move miles-wide chunks of rock   
   across a star system quickly, you no longer need the rock.   
   > >    
   > > 2.  Antimatter.  Very effective, if you have a supply of the stuff.  Less   
   radioactivity than the nukes, if you care about that (there'll still be a   
   little).   
   > >    
   > > Downsides - Hard to get (unless you have a natural supply somewhere) and   
   hard and incredibly expensive to make, unless you can do something funky like   
   using non-orientable wormholes or something).  It's a brass-bound bitch to   
   store, and dangerous to    
   you as long as you're storing it aboard, and storage of masses of antimatter   
   are fail-deadly.  Further downside is that other than lower radioactive   
   contamination, AM bombs don't do much that a fission and/or fusion device does   
   not.   
   > >    
   > > 3.  R-bomb.  Deadly effective, much like the asteroid bomb, but very,   
   very, very expensive.  If you don't have FTL it's as fast as any other attack   
   method, but if you do have it, it's not clear what advantage it offers over   
   'hold full of nukes'.     
   Maybe you accelerate something up to .99c and FTL it into position and let it   
   hit...but a 'hold full of nukes' still looks likely to be cheaper, and maybe   
   leave the planet actually in better shape to do something with afterward (if   
   you care about that).   
   > >    
   > > 4.  Big laser (or equivalent).  Yeah, it's doable, but if you want to   
   attack in reasonable time, you need to set up your infrastructure to generate   
   the big beam in the target star system, which takes time, effort, might give   
   the target time to do    
   something about it all, and is expensive.   
   > >    
   > > One advantage:  once you have your Big Laser Gun in the sky, you can   
   likely use it to pick off targets fairly precisely, esp. if you pick a   
   frequency that the local atmosphere will pass pretty well, or have so much   
   juice it can burn right through    
   anyway.  But if you're in the city-destroying mood, well, there again, the   
   nukes are probably faster and cheaper.   
   > >    
   > > Any see any solid advantage of the other attack methods over the nukes?   
   >    
   >    
   > Nukes are not easy to make. You need to mine out a mountain, refine the low   
   grade uranium from the ore, then refine the uranium to weapons grade.   
      
   Uranium is common, and the process is not that difficult. It would be easier   
   if done in vacuum and/or microgravity, both of which should be easily   
   available to a society which has cheap interstellar travel.   
      
      
   >    
   > You can also use plutonium, but that require breeder reactors that are also   
   expensive to build and run.    
      
   You do NOT need a breeder reactor to get plutonium. Having a breeder reactor   
   makes it easier, but there are other ways.   
      
   >    
   > Each of these steps cost in the hundreds of millions of dollars.    
      
   Chump change for a society which has cheap interstellar travel. And, in any   
   case, only that expensive if you insist on using primitive technologies.   
      
   >    
   > It is still the cheapest way of blowing up cities on earth, but if you have   
   star traveling capability, you will at the very least have fusion, and if you   
   have fusion, who will build and maintain the infrastructure necessary to get   
   the fissile materials?   
   , especially in the amounts needed for an interstellar bomb run.   
      
   If you have fusion, the possibility exists that you have direct fusion bombs,   
   with no need for the primitive technology of using a fission bomb as a first   
   stage.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)