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The Milky Way and Tyler Nordgren

The Milky Way and Tyler Nordgren
The Milky Way and Tyler Nordgren In March and April, the winter Milky Way sets in late evening while the summer Milky Way rises in early morning. At the transition between the two events, the Milky Way wraps around the horizon, provided you are near a latitude of 27 degrees north and have absolutely no sources of light pollution along the horizon. The darkest place in the United States with clean, dry air at that latitude is right here in Big Bend National Park. At 3:30 am I watch the Galaxy rise. Before me is the center of the Galaxy, 8,500 parsecs (30 thousand light years) away. To my left is Cygnus, the direction the Sun travels as it orbits the Galactic center. To my right is the direction from which we have traveled. The Sun makes one complete orbit every 250 million years or so. Notice the Milky Way looks dim and reddened near the horizon. This is due to dust in our atmosphere, just as the light of the rising or setting sun is red and dim. Now, however, it is the light of a billion sunrises.
(From Tyler Nordgren's Stars Above blog, March 2008)