From: wolfone@ccwf.cc.utexas.edu (Nobody of Importance)
Newsgroups: rec.arts.sf.science
Subject: Re: Invading planets
Date: 23 Jan 1993 23:25:16 GMT
Organization: The University of Texas at Austin, Austin TX
NNTP-Posting-Host: huey.cc.utexas.edu

In article <dpn2.227.727824956@po.CWRU.Edu> dpn2@po.CWRU.Edu (Damien P. Neil) writes:
]In article <1js764INN6q7@uxa.ecn.bgu.edu> mgcbo@uxa.ecn.bgu.edu (Charles B. Owen) writes:
]>Everyone is very much in love with dropping or throwing rocks in space.
]>Remember, though, that to drop that asteroid so that it can destroy a
]>city, it must have enough kinetic energy to destroy a city and that
]>energy has to come from somewhere.  It will not come from just falling
]>into the Earth's gravity well.  Text's such as Lucifer's Hammer assume
]>an object on an unrelated, but intercepting course.  That is not the
]>same as "dropping a rock".  Now many may say that we will just "divert"
]>a rock from the asteroid belt.  The energy required to do so will be
]>simular to that expended by the rock reentry.  So, you are not
]>accomplishing much.
]
]I'm not certain about this. In order to conduct interplanetary war there 
]must be, of course, interplanetary travel. The size of the "rock" being 
]dropped does not have to be very large; something about the size of one of 
]the spaceships being used should be fine. (Remember -- the ships will have 
]to be either numerous or large, in order to carry all the needed troops.) 
]What this means is that the technology used to move the invasion ships 
]should be able to be used on the "rocks". It might take a while to get 
]them to the planet being attacked (say 6 to 9 months?), but seiges have 
]lasted _much_ longer than that before.
]
]Attacking a planet might have a lot of parallels to besieging a castle, but 
]with some interesting differences. For example, you can park in a high orbit 
]and be relatively safe from attack from below; anything coming up should be 
]fairly simple to hit before it can reach orbit.

True. Which is why most high population worlds would probably have their
own fleet of warships to keep local space control. On an interstellar level,
the defending ships need not all be FTL-capable, while invading ships would
(assuming FTL is possible of course) need such drives and would be on the
wrong end of a supply line.

]Sort of like standing on top 
]of a cliff while people try to climb up and attack you; you can just toss 
]things down at them and knock them off.

Nice analogy. If you destroy all defenders in space as above.
 
]Does anyone know of any good invasion books other than _Lucifer's Hammer_? 
]This thread has piqued my interest.

_Footfall_ :) Or try some of the Joe Weber/Steve White novels. There are also
some science fiction RPGs and board games that have their own rules for
interstellar combat. I recommend Renegade Legion Prefect and any Traveller
sourcebook you can find on the subject.
 
]-----
]Damien Neil   dpn2@po.cwru.edu    "Until somebody debugs reality, the best
]Case Western Reserve University    I can do is a quick patch here and there."
]CMPS/EEAP double majoring masochist               - Erik Green

Subject: Patrick Chester            |Words to live by:
Age: NOYB                           |"Military action is important to the     
Address: A place                    |nation--it is the ground of death and     
Email:wolfone@ccwf.cc.utexas.edu    |life, the path of survival and destruction
Political Views: Somewhere in orbit |so it is important to examine it."-Sun Tzu
Blackmarks: Politically Incorrect   |Famous Last Words:                        
(hobbies)   Anime Otaku/Trekker     |--If you cut me down, I will only become
            Technocentric           |more powerful...  
            Netrekker (claypigeon)  |--Shhh!! There it is again....           
            Whole bunch of -isms    |--Use the bazooka to open the door...
     Won't remove Sun Tzu quote to  |--I cut the red wire...
     make the Greens happy ;)       |--I have a *very* bad feeling about this
-- 
<***** INSERT LAWSUIT DEFLECTION TEXT*****> 

I speak (type actually) for myself only. Even if I did decide to 
speak for UT, no one would listen. 

Flame away, I don't bleedin' care...
Xref: sparky rec.arts.sf.science:4251 rec.arts.sf.written:18276