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From: charles@utastro.UUCP (Charles Sandel)
Newsgroups: net.astro
Subject: StarDate: August 18
Message-ID: <414@utastro.UUCP>
Date: Mon, 20-Aug-84 11:42:09 EDT
Article-I.D.: utastro.414
Posted: Mon Aug 20 11:42:09 1984
Date-Received: Wed, 22-Aug-84 02:47:02 EDT
Distribution: net
Organization: UTexas Astronomy Dept., Austin, Texas
Lines: 44


It's worth a trip to the country to see
the summer Milky Way.  More about it --
right after this.

August 18:  The Milky Way

If you go into the country this month, 
plan for a moonless night when the air is clear and still.
Look overhead -- and there you'll see a hazy starlit band arcing across the
sky -- the glittering arc of the summer Milky Way.

If you have binoculars, you can prove to yourself that the haze is really
stars -- countless stars blurred together over colossal interstellar distances.
These stars only appear close together because they're very far from Earth.

When we look at the Milky Way, we're looking into the plane of our own galaxy.
We see the Milky Way as a starlit trail spun across the sky -- but it's 
really a huge star-island with a compact center and winding spiral arms.
The Milky Way is a so-called spiral galaxy -- one of billions in the universe.

In summer, our night sky is turned so that we face toward the center of our
own galaxy.
The galactic center lies due south in August, 
in the direction of the constellation Sagittarius.  
In a dark sky, you can see that the starlit trail 
widens in the south into a broad boulevard of stars.
It's tempting to imagine that these very stars reside in the galaxy's core.
But they don't.
The actual center lies some 30 thousand light-years from us and is wholly
obscured by impenetrable clouds of gas and dust.
When we look southward in the August sky, we're really seeing stars in the next
spiral arm inward from ours, called the Sagittarius Arm.

Script by Deborah Byrd.


(c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin
-- 

                     *>> Charles Sandel <<*
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