October stargazing is fantastic
Normally I do this monthly star map column toward the first of the month, but last week I wanted to write about the 2017 edition of the harvest moon. It’s bright light makes it hard to see much of anything very well anyway. This week we’re getting our dark evening skies back!
It’s really autumn now, and it’s a really wonderful time to get out and enjoy the absolute beauty of the night sky. We’re entering the prime time of stargazing season. The nights are longer, the mosquitoes are pretty much toast, and with less moisture in the air the skies are clearer. Even if you’re not a big- time stargazing fan, you owe yourself the treat of lying back on a reclining lawn chair and taking in the celestial happenings. The dark skies of the countryside are best, but it’s even a great show right from your own backyard.
Even though summer is long gone there are still many stars of summer hanging on in the western Marshall sky after evening twilight. You can still easily see the Summer Triangle high above the western horizon with the three bright stars from three separate constellations. The brightest shiner is Vega in the constellation Lyra the Harp. In second place for brilliance is Altair in Aquila the Eagle. The third brightest nuclear fusion furnace is Deneb in another bird constellation, Cygnus the Swan. Cygnus is also known by many stargazers as the “Northern Cross,” because at first glance that’s what it really looks like. Deneb is at the top of the cross, and below you can see three dimmer stars that make up the crosspiece of the cross. Roll your eyes a little ways below the crosspiece and look for an equally bright star at the foot of the cross. That’s Albireo.
You definitely want to check out Albireo with binoculars or a small telescope. You’ll like what you see here. Albireo is actually a double star. One star is gold and the other is blue and you can really see these colors. The two stars look like they are right next to each other, but many astronomers believe they are about one light-year apart. Astronomers don’t know for sure, but Albireo may be a binary system. The two stars could be orbiting each other in a period of around 100,000 years. I don’t think you want to stay to see that!
The Big Dipper is upright and riding low in the northwestern sky. In fact, it’s getting so low that it’s hard to see if you have a high tree line. The Big Dipper is the most famous star pattern there is, but it’s technically not a constellation. The Big Dipper is actually the rear end and the tail of the constellation Ursa Major, the Big Bear. It’s also the brightest part of the Big Bear.
One of the pieces of star lore that I love involves the Big Bear and the nearby constellation Bootes, the hunting farmer. By this time of the year Bootes is only partially visible above the northwest horizon, but this farmer Bootes has been hunting down the Big Bear all summer long. He’s finally laid some pretty good shots into the beast and that’s why it’s falling so low in our sky. The Big Bear is bleeding and as the blood falls on the trees and bushes it causes them to turn red. Forget about the leaves losing their chlorophyll. This is how we actually get our fall colors…wink-wink, nod-nod.
Over in the eastern skies is the grand constellation Pegasus, the winged horse. Look for a giant diamond of stars on the rise in the east. Just to the upper left of Pegasus is the Andromeda Galaxy, the next door neighbor to our Milky Way, nearly 2.5 million light- years away, with just one light-year spanning nearly 6 trillion miles!
Unfortunately the only planet available in the evening is Saturn, but not for long. In the first part of October, Saturn pops out in the later part of twilight very low in the southwestern sky and sets shortly after darkness sets in. Because it’s so close to the horizon it will be super blurry in any sized telescope. By the end of the month it will already be below the horizon by sunset. During early morning twilight the planets Venus and Mars are in a super tight celestial hug in the low eastern sky, separated by less than a degree. That’s less than the width of one of your fingers held at arm’s length. It’s quite a show!
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 at http://www.adventurepublications.net.