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Ohio Polo Classic set for this Saturday

August 14, 2011

My first experience with amateur astronomy was not a good one. I couldn’t find anything in my crude, home-built telescope.

I had heard that members of the astronomy club did their stargazing at a site north of Columbus. I decided one clear night to go there and ask for some help.

When I got there, I had to carry my scope down a long, dark, wooded path. Ahead was an opening in the trees, and the memory of what I saw in it still brings a lump to my throat after all these years. The opening was full of stars.

As I got closer, I saw the dark silhouette of a dozen or so people huddled over their telescopes against the backdrop of the brilliant glow of the Milky Way in the constellation Sagittarius, the Archer.

Sagittarius looks more like a teapot than an archer, and that’s how most stargazers recognize it these days. But even that image doesn’t work for most members of the latest generations. Tea comes in bags now. Not too many people use teapots anymore.

Newcomers tend to attract a lot of attention at these informal “star parties.” Where had I gotten my scope? Had I built it myself? Would I like to see something in it?

Would I!

They gave me the grand tour of the sky, with emphasis on Sagittarius, which is laden with so-called “deep-sky objects.” They are astronomical objects like star clusters and gaseous nebulae that are out beyond our solar system.

Sagittarius is in the direction of the center of the galaxy where the Milky Way is densest with stars and the hydrogen gas they are formed out of.

They started with the globular cluster M22, just to the left of the top of the “teapot.” In binoculars it is a small, round fuzzy spot. In my telescope, it exploded into a ball of countless small stars.

Next they showed me M28, which is just above the tip of the lid of the teapot. It is a smaller, fainter version of M22.

After that we looked at M8, the Lagoon Nebula, which is right above the spout of the teapot. In binoculars it looks like an oval hazy patch. In the telescope, it looked like a large milk spill with a long, dark, lagoon-like indentation at its center.

The Lagoon is an “emission nebula,” a stellar nursery where new stars are forming out of the raw hydrogen of the galaxy. Slowly, parts of the hydrogen gas in the Lagoon are collapsing by gravity into balls of hydrogen. When the pressure is great enough, the hydrogen begins to form helium in a giant thermonuclear reaction that will last perhaps 10 billion years.

Just above the Lagoon is M20, the Trifid Nebula. It is another stellar nursery. It gets its name from the dark lines that split it into three parts, like a cosmic peace symbol.

Nebulae are the reasons that stars tend to be found in clusters. Many stars are created out of a single, gigantic cloud of hydrogen. When the stars have formed and the remaining gas has dissipated into space, we are left with many stars close together.

Such “galactic clusters” are found in great abundance in Sagittarius. They showed me M21, dozens of stars that are visible in the same telescope or binocular field as the Trifid Nebula. They also showed me M25, a cluster of about four-dozen stars. It’s up and to the left from the lid of the teapot and is bright enough to be seen in a small ‘scope or binoculars.

Up and to the right from M25 was M24, which was much larger than the other objects. M24 is a “star cloud” of the Milky Way, a dense aggregation of stars, star clusters and hydrogen clouds. We swept slowly across its length in my telescope.

Directly above M24 was M18, a small cluster of about a dozen stars.

Above M18 was another glowing emission nebula called M17. It looks like a ghostly checkmark floating in space.

The tour of the area ended with a glimpse of another nebula, M16, right above M17. M16 is called the Eagle Nebula because it has a small dark patch in it that resembles a flying eagle.

Driving home, I felt myself a part of a universe so grand and complex that my mind was incapable of grasping it.

But my heart understood.

In case you haven’t guessed, that place — the place where my love of the starry vault became permanently fixed — was Perkins Observatory.

If my obsession with protecting that place from the growing stain of light pollution seems unusually obsessive, please note: Every time we show newcomers the stars, we do for them what humans have done since they first looked up at the sky. We pass the knowledge of the heavens on to the next generation.

In doing for other beginners what my mentors did for me, I pay back a tiny portion of the debt I owe them, a debt I can never repay. But, by heaven, I will certainly try.

Tom Burns is the director of Ohio Wesleyan University’s Perkins Observatory. He can be emailed at tlburns@owu.edu.