Dancin’ Through the Milky Way

There are many advantages to living here in the Ozarks (and a few disadvantages, too—I’m looking at you, CenturyLink, you and  your crappy broadband), but there’s one that most folks who live here never consider. In a world filled with light pollution, we still have dark skies, at least over large swathes of the Ozarks.

Those really dark areas correspond pretty closely with the locations of National Park Service and, especially, US Forest Service land. There aren’t any cities of any great size—West Plains is one of the bigger spots of yellow in the middle of all the blue and gray and it’s population is only around 12,000. Most towns are 1,000-3,000 at most and the rest of the area is even less densely populated. Shannon County has a population density of 8 people per square mile.

I live right on the border of one of the blue and gray areas near Van Buren. My sky is dark enough that I can walk outside at night and, if the clouds coöperate, see the Milky Way in all it’s glory. If you’re not familiar with the Milky Way, it’s the fuzzy, indistinct (milky!) white band that runs from Cassiopeia in the north to Crux (a constellation which contains the Southern Cross) in the south.  However, at our latitude, anything south of Sagittarius/Scorpius is below the horizon and, obviously, can’t be seen.

The Milky Way is a barred spiral galaxy, some 120,000 light years across and containing at least 200 billion stars, but it looks like a narrow band to us because we’re looking at it from inside, seeing it edge-on.  The center or heart of the galaxy is located in the constellation of Sagittarius, with Scorpius just to the west.

The dark band that divides the Milky Way, roughly north to south, is an area of dust clouds known as the Great Rift. This can most easily be seen near Sagittarius, where it obscures the galactic center. The dust blocks light in the visible spectrum, but not infrared and other wavelengths, so astronomers have the means to see though the dust and peer into the heart of the galaxy.

To photograph the Milky Way you need the aforementioned dark sky, a camera that handles high ISO without generating a lot of noise, a lens with a large aperture and a sturdy tripod. All of the photos here were shot with a Nikon D7100, a Rokinon 14mm lens on a Sunpak tripod, on which I hung 15 pounds of weights to stabilize it as much as possible (I knew there was a reason I bought that set of weights!)

I almost always set the camera to f/2.8 (the widest aperture of my lens), 3200 ISO (any higher and I start getting unacceptable levels of noise) and a 25-30 second exposure. A thirty second exposure is really pushing things and I start to get star trails, even with the 14mm lens (which is actually a 21mm on the D7100’s crop sensor.) For White Balance, I either use the “Tungsten” preset or a custom setting of 3850 kelvin. Either way, there’s always a lot of post work in Lightroom and Photoshop before I’m happy with an image.

Some part of the Milky Way is visible all year, but the brightest part is best seen and photographed in the summer. During winter, the Sun is in Sagittarius so that part of the Milky Way is “up” in the daytime. Right now, you can just catch the galaxy’s heart immediately after sundown. Another week or two and it will be gone until next spring, along with your chance to see it.

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