Western Slope Skies - 7/18/14

Jul 18, 2014

The Evening Sky in Late July

The Sun sets late on these long summer days, and it’s not fully dark until almost 10 PM.  And, because of this week’s late-rising moon, the sky remains dark long after twilight, allowing us great views of the Milky Way and the stars of summer.

But, stars, which are distant suns, are not the only sights in the sky.  After twilight, the planet Mars shines reddish-orange in the southwest, just east of the blue-white star Spica.  And, you can find the planet Saturn by looking south-southwest, between Mars and the reddish star Antares further east.  If you have a telescope, take a look at Saturn and you’ll see that its ring system is now tipped at a high angle towards us.  So it’s easy to see Saturn’s beautiful rings, even in a small telescope.

Compare Mars to the reddish star Antares in the constellation Scorpius, the scorpion.   Which appears redder?  And, is Mars or Antares brighter this week?  The name Antares derives from ancient Greek and is often translated as “rival of Mars.”

You may see a hazy glow, extending from the tail of Scorpius near the southern horizon through the eastern and northeastern sky.  This is the Milky Way, a band of billions of distant suns, dust and gas that delineates the disk and spiral arms of our home galaxy.  The Milky Way appears brightest toward the constellation Sagittarius, low in the southeast on July evenings.  This is because the center of our galaxy lies in the direction of Sagittarius, and millions of stars and numerous clouds of glowing gas crowd this region of space.  A star chart, planisphere, or smart phone app may help you navigate the beautiful night sky of early summer.