When stargazing, there are two main arcs across the sky that are important to pay attention to. These arcs are always in the sky, and understanding them will make your sessions much more successful, even without a telescope or pair of binoculars!

In this column, I will discuss the first of these arcs — the Milky Way. Stay tuned for my next piece, where I discuss the second arc — the ecliptic.

The Milky Way galaxy is a collection of 100 to 400 billion stars. Our sun is just one of these stars, situated near the edge of the galaxy, far from the center. Even on a perfectly clear night, you won’t be able to see more than 1,000 stars with the naked eye. Every time you’ve looked in amazement at an uncountably large number of stars, you were only seeing a tiny fraction of the total stars of the Milky Way. All of these stars, indeed every star you will ever see, even through a telescope, are inside the Milky Way.

The Milky Way formed roughly 13.5 billion years ago, and it has been continuously revolving. Our sun takes roughly 250 million years to orbit the Milky Way. Just like how a ball of pizza dough flattens out as you spin it in the air, the Milky Way has also flattened out into a disk.

The Milky Way running through the Summer Triangle and the constellation Cassiopeia. (Photo courtesy Wikimedia Commons)

If you were to look at the Milky Way from above, it would look like a pizza: circular, with some thickness. However, since we live in the Milky Way, we can only view it from the inside. If you lived inside a pizza, you would see it as a thick band encircling you. Likewise, on Earth, we see the Milky Way as a glowing band encircling us. Even stars that don’t appear to be in this band are still inside the Milky Way. Since the galaxy has some thickness, there are neighboring stars all around us.

The Milky Way is a breathtaking sight. However, due to light pollution, over 80% of Americans cannot see it. The dark skies of the Adirondacks are incredibly valuable, and make the region one of the few places on the East Coast where you can see this astronomical treasure.

Humans have been marveling at the Milky Way for millennia and creating countless stories related to it. In Babylonian mythology, the Milky Way was seen as the severed tail of a saltwater dragon. The ancient Greeks believed it was a streak of spilled milk.

There are also many stories related to the stars in the Milky Way; for example, the Greek constellation Cassiopeia. According to myth, Cassiopeia was a vain Ethiopian queen and mother to Andromeda (a neighboring constellation). The constellation is very well known due to its distinctive W or M shape. On a hazy night, if you’re having trouble finding the Milky Way, you can follow the shape of Cassiopeia to try and make it out.

In the summer, you can also spot the Milky Way by looking for the Summer Triangle. This large asterism (a star pattern with fewer stars than a constellation) contains three of the brightest stars: Vega, Deneb and Altair. If you can spot these three stars, the Milky Way runs right through them. An ancient Chinese myth states that Altair was a human who fell in love with a cosmic princess, Vega. They longed to be together, but Vega’s parents forbade it. Her parents turned the Milky Way into an impassable river which separates Altair and Vega, even to this day.

Whether you are drawn to the Milky Way for its beauty, its cultural significance or its scientific intrigue, enjoy this spectacular sight!

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Simon Thill is the Associate Director of Astronomy Outreach at the Adirondack Sky Center & Observatory in Tupper Lake. Their organizational vision is to inspire curiosity and provide perspective on our Universe through wonder and enlightenment.