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From: barnes@INFINET.UUCP (Jim Barnes)
Newsgroups: net.space
Subject: Re: nearby supernovas etc.
Message-ID: <8603061510.AA04282@infinet.UUCP>
Date: Thu, 6-Mar-86 10:10:05 EST
Article-I.D.: infinet.8603061510.AA04282
Posted: Thu Mar  6 10:10:05 1986
Date-Received: Sat, 8-Mar-86 05:01:46 EST
References: <8603020306.AA00249@s1-b.arpa>
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Organization: Infinet, Inc.
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In article <8603020306.AA00249@s1-b.arpa> you write:
>By the way, in latest Sky&Telescope there's a note on Sirius being
>reddish in recorded history (in fact about 600 AD), because at that
>time its white-dwarf companion was in the red giant stage. It's hard
>to believe the conversion from red giant to white dwarf could occur so
>quickly, although with Sirius gobbling most of the loose hydrogen as
>fast as it is shed, and ionizing & light-pressure-shoving the rest of
>the emitted hydrogen, I could imagine it within the realm of
>possibility. Any news since S&T publishing date on that topic that you
>know of?
>

I recently (two months ago?) read an article in the Boston Globe
that said roughly the same thing - Sirius was reddish within recorded
history.  I posted the same question to net.astro.  The general response
received was that the redness was due to the time of day when the
observations were made.  ie. Sirius sets near the sun during the dog
days of the summer, hence the reddish color is due to the sunset, not
the color of the star.  Current theories of stellar evolution do not
allow for a star to evolve that rapidly.
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decvax!wanginst!infinet!barnes 		Jim Barnes