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From: neal@denelvx.UUCP (Neal Weidenhofer)
Newsgroups: net.astro
Subject: Re: StarDate: June 11 Where the Stars Don't Twinkle
Message-ID: <71@denelvx.UUCP>
Date: Sat, 22-Jun-85 14:09:43 EDT
Article-I.D.: denelvx.71
Posted: Sat Jun 22 14:09:43 1985
Date-Received: Wed, 26-Jun-85 05:15:38 EDT
References: <224@utastro.UUCP>
Organization: Denelcor, Aurora, Colorados
Lines: 30

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> 				The twinkling we notice from the ground
> comes from the effect of the atmosphere on incoming waves of
> starlight.  The atmosphere makes the light waves ripple -- incoming
> waves from a single star interfere with each other as they descend
> through Earth's blanket of air -- to our eyes.  This rippling produces
> the brightness and color changes which we see as the twinkling of the
> stars.
> 
> (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin

	This brings to mind a question that's been on my mind for a number
of years:

	Given that the twinkling effect is caused by tthe atmosphere as
stated above, why is it that the stars twinkle but the planets don't.

	The explanation I've always heard is that it's because the planets are
closer--but I don't see what that has to do with it; after all, they aren't
closer than the atmosphere.  (Are they? :-)

	In other words, why does the atmosphere have that effect on
starlight but not on the light reflected from the planets?

And while the future's there
	for anyone
To change, still you know it	Regards,
	seems				Neal Weidenhofer
It would be easier sometimes		Denelcor, Inc.
	to change the past.		!denelcor!neal