We Still Have Summer Skies in September!
Summer is its final phase. Schools are opening or already open, and I even spotted a few Halloween decorations going up in a department store. If you're like me you hang on to summer as long as you can, and one way to do that is September stargazing. There are still plenty of summer constellations playing on stage in the celestial theater and being that it gets darker earlier your sleep deprivation is reduced.
Early this week we start out with a lovely waxing crescent moon in the western sky that sets shortly after sunset. As the week goes on the crescent grow into a first quarter half moon that starts out the evening farther to the east in the heavens. Full Harvest Moon this is late next week on the 16th so get your prime stargazing in this week before our lunar neighbor white washes the heavens!
In the low southwestern are the only two planets we can easily see this month, Mars and Saturn. They've actually been in our skies all summer but now they're getting ready to make their exit. They're the two brightest starlike objects close together in that part of the sky. There's a fair bright reddish star below them that's Antares, the bright star in the constellation Scorpius the Scorpion that's now only partly above the southwest horizon.
Despite its brightness there's not much to see on Mars with even a larger telescope. It's a small planet and the separation between Earth and the red planet is widening at over 90 million miles. On the other hand Saturn's great to look at even with a smaller telescope. Without any trouble you should be able to make out Saturn's giant ring system. The bad news is that since it's so close to the horizon the Earth's atmosphere will have more of blurring effect. It's still worth a look though! This coming Thursday and Friday evening to moon will positioned just above Saturn and Mars.
Just to the left of Scorpius, Mars, and Saturn is one of my favorite constellations, known by many as the Teapot. Now for you purists the teapot is formally known as Sagittarius, a centaur shooting an arrow at Scorpius to its west. If you see Sagittarius as a half man-half horse with a bow and arrow, more power to you! I'll stick with the Teapot.
The Teapot is located in the direction of the center of our Milky Way galaxy, a little around 30,000 light-years away. If the sky is dark enough where you are, you'll see a milky white band of light from the Teapot in the southwest sky that runs all the way across to the northeast horizon. You're looking at the combined lights of billions of distant stars that make up the main plane of our galactic home.
Nearly overhead is another signpost of summer, the Summer Triangle. Just look for the three brightest stars you can see around the zenith and that's it. All three stars are the brightest stars in each of their respective constellations. Vega is the brightest star in the constellation Lyra the Harp. Altair is the brightest in Aquila the Eagle, and Deneb is the brightest star in Cygnus the Swan, also known as the "Northern Cross".
There's nothing really all that "summer" about the Big and Little Dippers since they're visible every night of the year, but summer is a great time to spot them. That's especially true for the Big Dipper since it's proudly hanging by its handle high in the northwest. The fainter Little Dipper is standing on its handle to the right of the Big Dipper with Polaris, the North Star, at the end of its handle.
In the northeast sky look for the sideways "W" that outlines the throne of Cassiopeia the Queen. Just to the upper left of the queen in the northern sky look for the faint upside-down house with the steep roof, which is supposed to be Cepheus the King.
You can't deny the change in seasons forever. Autumn is coming. One of the prime autumn constellations, Pegasus the winged horse, is on the rise in the eastern sky after sunset. Look for the big diamond of stars that outlines the torso of Pegasus. This is called the "Square of Pegasus", but because of the way it's positioned in the sky this time of year it's also known as the "Autumn Diamond."
Below and to the left of the Autumn Diamond, scan with a decent pair of binoculars for a faint patch of light. If you see it, you are looking at our galaxy's next-door neighbor, the Andromeda Galaxy, more than 2 million light-years away. Keep in mind that just one light-year equals almost 6 trillion miles!