September nights are expanding
Butler summer stargazing can be so comfortable!
However, for many folks with Monday-through-Friday jobs, early wake-up calls restrict extended nights under the stars to the weekends. In September though, nightfall begins much earlier, especially toward the end of the month. Along with that, there are still plenty of comfortable evenings in September.
The summer constellations still dominate the early evening sky with the “Summer Triangle” dazzling nearly overhead as soon as evening twilight ends. Just look for the three brightest stars near the zenith, and you’ve found it. It’s one of the best tools for helping you navigate that part of the sky because the three stars you see — Vega, Altair and Deneb — are all the brightest stars in their respective constellations: Lyra the Harp, Aquila the Eagle and Cygnus the Swan.
Another great summer constellation, Boötes the Herdsman, shines proudly in the early evening western sky. It looks just like a kite with the super bright star Arcturus marking its tail. Arcturus is the brightest actual star we see in the summer skies.
A truly summer classic is the constellation Sagittarius the Archer in the low southern sky. According to Greek mythology, Sagittarius is allegedly a centaur shooting an arrow. A centaur is a creature that’s a man from the waist up and a horse from the waist down, complete with a tail. If you see that, gazing at Sagittarius, I want to party with you. What it really resembles is a teapot that’s so easy to see, even in light-polluted areas.
Look for the Big Dipper proudly hanging by its handle in the northwest. The Big Dipper isn’t an official constellation, but it outlines the rear end and tail of the great constellation Ursa Major, the Big Bear.
The fainter Little Dipper, otherwise known as Ursa Minor, the Little Bear, is standing on its handle to the right of the Big Dipper with Polaris, the North Star, at the end of its handle. Everything in our celestial dome rotates around Polaris every 24 hours because it shines directly above the North Pole.
If you’re lucky enough to stargaze in the countryside, you can’t help but notice that ghostly ribbon of light that bisects the sky from the north-northeast horizon to the south-southwest. You’re enjoying what’s known as the Milky Way band, the thickest part of the disc-shaped plane of our home Milky Way galaxy.
The center hump of our home galaxy lies in the general direction of the three stars that make up the teapot spout in the constellation Sagittarius. That area of the Milky Way would be much brighter in our night sky, but opaque clouds of interstellar gas and dust block our view.
As far as evening planets, Venus is still visible in the low western sky, popping out during evening twilight and setting not long afterward. The planet named after the Roman goddess of love is in the later stages of a long goodbye from our evening sky and will become the “morning star” in November.
Even with a telescope, there’s honestly not much to see, as Venus is completely shrouded by a thick and poisonous cloud cover. What you may be able to resolve, though, is that Venus is now in the shape of a crescent moon, but it’ll definitely appear fuzzy because it’s so close to the blurring effect of Earth’s thicker atmosphere near the horizon. On Sept. 13 and 14, the new crescent moon will be hanging around Venus along with the moderately bright star Spica.
As Venus says goodbye to the evening, Saturn says hello! By 9 p.m. in early September — and even earlier toward the end of the month — the great planet Saturn emerges above the eastern horizon. It’s nearing its closest approach to Earth for 2026. It’s always great to view Saturn, even with a small telescope.
If you want to excite a young person in amateur astronomy, show them Saturn through a telescope. I guarantee that they’ll love what they see. Over the years, I’ve seen this happen so many times with kids. Just make sure you let Saturn get above the horizon enough to eliminate the blurring effects of Earth’s atmosphere. That’ll make for a late night early in the month, but much earlier toward the end of the month.
Even with a small telescope, Saturn’s gorgeous ring system will blow you away. It’s more than 150,000 miles in diameter but only about 50 feet thick, on average. You should also see some of Saturn’s moons, resembling tiny stars around Saturn. Titan is Saturn’s largest moon, over 3,200 miles in diameter, with a thick methane atmosphere. On Sept. 26, Saturn follows closely behind the full moon in the early evening as they rise above the eastern horizon.
Autumn officially begins with the autumnal equinox. This year, it’s on Sept. 23 at 00:05 Universal Time (UT). The northern and southern hemispheres will experience nearly equal amounts of daylight and darkness that day. From then until Dec. 21, the sun’s daily path across the sky sinks lower and lower in the northern hemisphere and higher in the southern hemisphere.
A few days later, on Sept. 26, we’ll have a full moon, and by definition, since it’s so close to the autumnal equinox, it’s the full harvest moon for 2026, as it falls within 10 days of the equinox.
Enjoy September stargazing splendor!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is also the author of “Stars: a Month by Month Tour of the Constellations,” published by Adventure Publications and available at bookstores and at adventurepublications.net. Contact him at mikewlynch@comcast.net.
