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From: leech@Apple.COM (Jonathan Patrick Leech)
Newsgroups: sci.astro,sci.space,sci.space.shuttle
Subject: Re: asteroid almost hits earth
Message-ID: <31429@apple.Apple.COM>
Date: 23 May 89 18:10:43 GMT
References: <256@ringwood.Morgan.COM> <3200009@hpindda.HP.COM> <4566@tekigm2.MEN.TEK.COM> <2635@ssc-vax.UUCP> <103026@sun.Eng.Sun.COM> <6101@nfs4.rl.ac.uk>
Organization: Apple Computer Inc, Cupertino, CA
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In article <6101@nfs4.rl.ac.uk> kgd@inf.rl.ac.uk (Keith Dancey) writes:
>My understanding is that the demise of the dinosaurs extended over a period
>of order of magnitude of a thousand years.  Certainly long enough to place
>doubt upon the viability of a single catastrophy such as the one mentioned.
>If the palaeontological evidence is not contradicted (and I have understood
>it correctly) then a *series* of such catastrophic strikes would be required.
> 
>That is not say a single catastrophy is ruled out, but it looks as though
>its effects must be longer-lived than a few years.

	There is some belief that a gravitational perturbation of the
cometary cloud could produce "showers" of comets in the inner solar system.
Don't take "showers" too literally - it means a handful of hits over
long periods of time - but this has some bearing on your comments.

	Yow! Get off the net for two weeks, come back to 600 articles in
sci.space. :-)

	Jon Leech (leech@apple.com)
	Apple Integrated Systems, San Jose
	__@/