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See the Milky Way Galaxy From Earth: October is the Best Time

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Ethan Richardson/Unsplash
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The Milky Way is Straight Up Right Now!

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If you鈥檝e ever wanted to see the Milky Way galaxy from Earth, late September through October is your window of opportunity! Right now, we鈥檙e aimed toward the most concentrated part of the Milky Way. Learn more to see the kind of inspirational, star-filled panorama experienced in planetariums!

If you live鈥攐r can visit friends鈥攊n a rural location away from city lights, October can be very special. It鈥檚 when amazing things hover straight overhead. Spread a blanket or set up a deck chair and gaze up anytime after dinner, say around 8 p.m.

Lunar brightness won鈥檛 be around before midnight after October鈥檚 first week, and the sky will be totally moonless mid-month, making for a perfect 8 p.m. sky session. Star-filled planetarium conditions will linger until the approach of the Hunter鈥檚 Moon near the end of the month.

So what鈥檚 straight up?

It鈥檚 the Milky Way, which splits the sky from north to south and crosses the heavens overhead! A century ago, it was widely believed to be the entire cosmos. Now we know that our Milky Way galaxy is just one of hundreds of billions that make up the universe.

What is the Milky Way?

Of course, the Milky Way is our home galaxy. It a 鈥渂arred spiral鈥 type of galaxy with giant spiral arms that make it look like a spinning pinwheel. It includes our solar system and Sun, which is located on a smaller spiral arm, about half the distance from the center of the galaxy to its outer edges. While we on Earth orbit the Sun, our solar system鈥檚 one-and-only star orbits the center of the Milky Way!

Why is it called the Milky Way? This describes our galaxy鈥檚 appearance from planet Earth: a hazy, milky band of light stretching across the night sky. No one knows where the name came from, though the ancient Greeks used the word galactos to refer to milk; and there is a Greek myth about the goddess Hera who sprayed milk across the sky. Ovid, a Roman poet, later wrote about the Milky Way in 鈥淭he Metamorphoses鈥 in 8 A.D.

How Many Stars are in the Milky Way?

It鈥檚 estimated that there are several billion stars in the Milky Way Galaxy. All the stars you see from Earth are part of our home galaxy. However, how many stars you can see from Earth depends on the time of year!

Right now, in late September through October, we鈥檙e facing the highest concentration of stars. The Milky Way neatly splits the sky and passes directly overhead. The Moon is absent, so rural places away from city lights provide perfectly dark conditions, while early fall鈥檚 typical crisp, dry air affords the kind of transparency that allows the countless subtle details of the Milky Way to emerge in all its glory.

It鈥檚 a far cry from the spring, when the Milky Way is almost coincident with the horizon and invisible. Then, the sky offers only a smattering of stars to see. Ever noticed this? 

Best Time to See the Milky Way

From September to October: The Milky Way is visible in the evening.

Look straight up! We鈥檙e aimed toward the most concentrated part of the Milky Way Galaxy. 

  1. Look between 8 p.m. and 10 p.m. in the evening, looking up and towards the south.
  2. View on a new Moon or within a few days of the new Moon. See the Moon Phase Calendar for your area. Or,  check when the Moon will rise and set.
  3. Check for clear skies. It will be hard to see much on a cloudy night. Here鈥檚 the 5-day weather forecast.
  4. Go to a dark place with no lights. Frankly, with light pollution, the Milky Way is all but invisible. From non-light-polluted places, it鈥檚 a wonderland.

When you do get to see the Milky Way on a dark, moonless night and in its full splendor, it鈥檚 very hard not to be in complete awe. It鈥檚 humbling and, for many, spiritual. It feels like stepping back to an ancient cosmos before lights existed. 

Lately, wide-angle photos of nighttime landscapes with the Milky Way filling the sky keep appearing on the internet. It鈥檚 as if the starry glow of our galaxy鈥檚 edgewise portion has suddenly been discovered after a long absence. In truth, long exposures made with expensive equipment, and taken in areas with an inspirational foreground like from Arches National Park, are indeed gorgeous.


Image: Arches National Park. Credit: NPS/Chris Wonderly

However, some of us, like myself, whose house is in a state park where the nearest village has a population of 153, can get the experience by merely turning off the house lights and stepping into the backyard.

And now is the best time to do that.

Places to See the Milky Way Galaxy

In terms of place, you simply need dark skies! Drive out to the country one evening or on the weekend. With most of the world now living in cities, the full impact of the Milky Way often requires overnight camping at some very rural site. Usually, driving inland away from a city is your best bet. If you鈥檙e willing to travel, .

From a dark location, it takes about 20 minutes for human eyes to become fully sensitive to faint light. Away from the lights of town, lie on a blanket or lounge chair (reclining helps ease neck strain). You will witness the combined light of uncountable stars populating the dense, central hub of the Galaxy. These suns are so concentrated that you see billowing 鈥渃louds鈥 of stars!  

TIP: When you view the Milky Way, try looking through a camera which can accumulate light that the naked eye can not. .

How to See the Milky Way

Looking toward the dark skies at the right time of year, the naked human eye should see a whitish glow stretching in a huge arc. This band has been visible in the heavens since Earth first formed. This glowing line of light is the center of our galaxy, as seen from one of its spiral arms where we are located. It鈥檚 because our eyes cannot distinguish the individual stars that make up the glowing band of light that it all appears 鈥渕ilky.鈥 

Take 15 minutes to let your eyes adjust to the darkness. Then explore the creamy glow of the Milky Way, punctuated by patches of fuzz that binoculars show to be star clusters and gas clouds in our Galaxy鈥檚 spiral arms.  

Here, knowing the stars or constellations is as unnecessary as naming each trout in a stream.  But if you鈥檇 like to name something, well, that brightest star overhead at nightfall is Vega. (But say and think 鈥VEE-ga,鈥 not 鈥VAY-驳补.鈥)

Buried in that glow straight up at 8 p.m. hovers Deneb.  It鈥檚 not as brilliant as Vega, which is very high though not perfectly straight up.

But Deneb is special. It鈥檚 one of our galaxy鈥檚 most luminous stars, shining with the light of 60,000 Suns! Only its vast distance of 1,500 light-years keeps it from lighting up the countryside like a street lamp. And it happens to mark the direction toward which our entire solar system is zooming. (Read my post, 鈥Where in Space Are We Headed?鈥)

Our own Sun, taking us along for the ride, will reach that area around Vega and Deneb, that straight overhead territory, in about a million years. But since those stars are moving away from us like horses ahead of us on a carousel, we鈥檒l never actually catch them.

And low in the south where the Milky Way has a brightening and a bulge, that鈥檚 the center of our galaxy. It鈥檚 the amazing place around which every star, including our own Sun and its retinue of planets, revolve once every 225 million years.

To the ancient Peruvians and Mayans, the Milky Way was the center of the universe. And even in our Space Telescope age, it鈥檚 still the heart of ours鈥攐ur resident galaxy, observed not from the outside but from our worms鈥 eye viewpoint within its pinwheel motif.

Video: Zooming in on the heart of the Milky Way

This video by the European Southern Observatory (ESO) starts with a broad view of the Milky Way. We then dive into the dusty central region to take a much closer look. There lurks a 4-million solar mass black hole, surrounded by a swarm of stars orbiting rapidly. We first see the stars in motion, thanks to 26 years of data from ESO鈥檚 telescopes. We then see an even closer view of one of the stars, known as S2, passing very close to the black hole in May 2018. The final part shows a simulation of the motions of the stars.

What else is up this month? See the October Night Sky Guide.

About The Author

Bob Berman

Bob Berman, astronomer editor for The Old Farmer鈥檚 蜜桃恋人, covers everything under the Sun (and Moon)! Bob is the world鈥檚 most widely read astronomer and has written ten popular books. Read More from Bob Berman