Stargazing Time is Expanding!
Summer stargazing can be so comfortable! However, for a lot of folks with Monday through Friday jobs, the wake-up call for work restricts extended nights under the stars to the weekend. In September though nightfall begins much earlier, especially later in the month. That's really good because this September is extra special because of the tight pairing of Jupiter and Saturn, and the dramatic brightening of Mars!
We start the month off with a full moon. In most locations it's not officially full until September 2nd, but for all practical purposes it will be full as it rises on the 1st. It's best known as the Full Corn Moon, a Native American nickname, since this is the time of year when corn is ready to be harvested.
After the first week of September bright moonlight will have vacated the evening skies and serious stargazing can really begin. As evening commences, you should easily see what I call the "celestial cat's eyes" of 2020. Jupiter and Saturn pop out in the south-southeast sky are less than ten degrees apart, less than the width of your fist held at arm's length. In some binoculars you might be able to get both planets in the same field of view. They're the closest they've been to each other in the sky in twenty years. As summer turns into autumn, the two planets will draw even closer to each other, setting up for a tremendous celestial hugging toward the end of the year.
Even though Jupiter and Saturn aren't as close to Earth as they were in July they're still a sweet sight, even through a small telescope. On Jupiter you can resolve the disk of the 88,000-mile diameter planet. You might also see some of Jupiter's cloud bands, and possibly even the famous Great Red Spot, a raging storm in Jupiter's atmosphere. For sure you'll see up to four of Jupiter's brightest moons that appear as tiny "stars" on either side of the Jovian giant. Saturn is also simply wonderful to gaze upon through a small telescope. You can easily see its famous ring system that spans over 140,000 miles in diameter, as well as some of its moons, especially Titan, that's larger than the planet Mercury.
As bright as Jupiter and Saturn are in September, Mars will end up stealing the show as the red planet draws closer and closer to Earth. As September kicks off, Mars will be above the eastern horizon by 10 pm with its bright, distinctive reddish hue. Mars rises in the east by 8 pm and will be even brighter than it was on the first of the month. On October 8th Mars will be less than 39 million miles from Earth. Mars and Earth won't be this close again until 2035!
Provided there's not a global dust storm on Mars, you may actually see the surface with a small to moderately sized telescope. I certainly don't want to oversell what you'll see on Mars though. It's still only a 4000-mile-wide planet, and even with higher magnification it won't even come close to filling up the field of view of your scope all.
The summer constellations still dominate much of the sky, with the "Summer Triangle" dazzling near the zenith as soon as evening twilight ends. Just look for the three brightest stars nearly overhead and that's 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 is Bootes the Herdsman. Bootes is perched in the early evening western sky. It looks just like a kite with the super bright star Arcturus marking the tail of the kite. Arcturus is the brightest actual star seen in the summer skies. Another summer classic is Sagittarius the Archer. That's easily found this year in the low southern sky a little to the right of Jupiter and Saturn. According to Greek mythology, Sagittarius is allegedly a centaur, a half-man half-horse shooting an arrow. What it really resembles is a teapot. Sagittarius lies in the general direction of the center of our Milky Way Galaxy.
Speaking of the Milky Way, you can't help but notice that ghostly ribbon of light that bisects the sky from north-northeast to south-southwest in the darker skies of the countryside. 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.
Enjoy the September star splendor!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul, and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications. Available at bookstores and online at www.adventurepublications.net.
If you have any astronomical questions or want me to write about something you’re seeing in the night sky drop me a line at firstname.lastname@example.org