From: mhorning@zeus.calpoly.edu (Mark E. Horning (Captain Neutrino))
Newsgroups: rec.arts.sf.science
Subject: Re: Wrecking an O'Neill (Was: Re: Wrecking a Planet)
Date: 10 Jan 93 23:17:53 GMT
Organization: California Polytechnic State University, San Luis Obispo

curt@quest.UUCP (Curtis Gibson) states
>>rwallace@unix1.tcd.ie (russell wallace) Writes:
>>As I explained in another article, a piece of gravel is not at all going
>>to drill a hole in a 1 billion ton O'Neill habitat. Even if it did, the
>>population presumably have sealed compartments to get into during raids.
>>Plus, your attack carrier will have to get reasonably close to throw the
>>gravel. Probably within range of the defensive armament, plus the
>>defenders will have interceptors, as well as lots of civilian ships that
>>can be armed and used as interceptors.
>>
>>--- early posts omitted ---
>>
>>The habitat's defensive armament (which can be of almost any desired
>>size and power output) can simply vaporize the rock a long way away.
>
>If your 1 billion ton habitat is like the ones I'm familiar with from
>all my reading, its a cylinder or sphere around 1 km in diameter.  
>The cylinder type is 3 to 5 diameters long.  It is spun to supply
>artificial gravity. Its main axis is lined up to the sun.  It has 3
>BIG windows, (1/3rd the circumference wide) in the sides, with big
>petal like mirrors to reflect sun light inside.  Thats 1/2 of the 
>inside area is windows.  It will be paired with a twin for stability.
>The end pointed at the sun will have the thickest rock and soil rad
>shield, maybe 10 m thick.  The 10 m rad shield will aford a 99.9999
>protection against hard radiation, figured from the rule of 90 %
>reduction per 5 feet or 2 m of rock/soil.  Else where there will be
>about 3-4 m of rock/soil for a 99.99 protection.
>
>There will be rivers and streams, ponds and lakes, trees, srubs and
>grass.  A wonderful place to live, I'll be the first to rent/buy a
>home on one.  But if someone is shooting at it, its the last place
>I'll want my tender little pink butt to be.
>
>We have artillery shells that will penetrate 10 m of rock/soil 
>to smash bunkers.  They are only travelling about 1000 m per
>sec to do that.  Any thing that get thrown/shot at the habitat
>is going to be going a lot faster, maybe on an order of 100 times 
>faster.  The rad shield is not going to keep out anything trying to
>get in.  And remember, 1/2 the area is window.  No 10 m or even 3-4
>m of rock/soil.  I can think of the problems of fusing the projectiles
>to keep them from passing clear thru the habitat before they explode!
>
>Senearo 1.
>We attack from sunward to mask ourselves in the powerful signal of
>the sun.  Their IR and radar is blinded.  We launch from 500,000 km
>out a salvo of 12 missiles at each habitat in the pair.  They are
>going to be travlling at 2 or 3 times the orbital velocity of the
>habitats.  Flight time is under a day or 2.  (Wheres an envlope when
>you need one 8^)).  As the missiles close with the habitats they are
>still hidden in the sun.  But as the missiles get very close they are
>bound to be detected.  Decoys and jammers are deployed.  The pack
>starts to bob & weave with the decoys and jammers.  The defenders
>start to take a toll of the decoys, jammers and the missiles.
>They have to shoot fast, the missiles are very close now, there are
>very few left.  The defenders destroy the last missile, huzzah!!!
>The habitats are saved!  But wait, all that junk from the missiles
>is still out there, speeding towards them at 100,000 m per sec.
>(I'm making a guestamint here 8^)).  The defenders have a few bad
>moments then remember they have 10 m of rock/soil the stop the junk.
>There is going to be some damage, but nothing serious.  The junk
>starts to hit.  Then a window explodes! followed by the other
>2 windows.  Guess what happens when a big chunk of missile
>penetrates the habitat going hypersonic?  The shock wave will blow
>out your windows as sure as an explosion.
>
>I submit that O'Neill habitats are not invulnerable.  They got windows.
>
>Curtis S. Gibson   curt%quest.UUCP@cs.umn.edu

	Well, i'd make the windows out of quartz, or maybee 2 metre
thick fuzed silica. Course, I wouldn't use missles to attack the thing.
I'd just build a big shotgun firing steel cubse 30 cm on a side.


Mark E. Horning, Physics 	A penny saved is a congressional oversite.	
mhorning@pan.calpoly.edu	Don't steal, the IRS hates competition.

If you can't love the constitution, at least hate the government.