Xref: utzoo sci.space:8355 sci.space.shuttle:2017
Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!amdahl!drivax!macleod
From: macleod@drivax.UUCP (MacLeod)
Newsgroups: sci.space,sci.space.shuttle
Subject: Nanoparticle pollution
Message-ID: <3991@drivax.UUCP>
Date: 18 Nov 88 21:31:29 GMT
References: <1988Nov11.213348.27877@utzoo.uucp> <1084@esunix.UUCP> <1271@cfa.cfa.harvard.EDU>
Reply-To: macleod@drivax.UUCP (MacLeod)
Organization: Digital Research, Monterey, CA
Lines: 23

In article <1271@cfa.cfa.harvard.EDU> wyatt@cfa.harvard.EDU (Bill Wyatt) writes:

:Both arguments are correct, really. Think of the problem in terms of
:momentum. Since simply breaking up debris into smaller particles means
:each one has a smaller momentum (mv), they should do less damage
:hitting anything. A particle already in orbit can only lose momentum
:as the orbit decays. 
:
:However, Henry is right for practical reasons. You would have to
:convert *every bit* of debris into almost microscopic particles before 
:you would no longer have to worry about them. Remember the paint chip
:that hit the shuttle window? If you have some really delicate
:satellites (e.g. exposed mirrors or reflecting mylar sheets), then even
:microscopic debris is probably a no-no.

Imagine a big cloud of nonreflective microsopic particles.  A shuttle or
other craft flys in, and *poof* their glass optical ports become opaque, and
the skin gets microbeadblasted. 

How small does a missle have to be before it packs too little mass to be 
dangerous in a collision, given local speed limits (sun's escape velocity)?

Michael Sloan MacLeod (amdahl!drivax!macleod)