Wednesday, August 22, 2012

The dark sky of Door County -- especially on the night of the new moon

The Dark Sky of Door County -- Especially on the Night of the New Moon

We arrived in Door County on the night of the new moon, so the clear, dark night sky above the peninsula that juts out between Green Bay and Lake Michigan was even darker than usual, a reminder to city dwellers like us of just how many stars are out there that we usually don't see. When you look up at the Great Dipper in Madison, it really stands out because you don't see all that many other stars. In Door County it was almost lost in the stars.

Milky Way Over Door CountyThis is looking north across Green Bay from Gills Rock, at the tip of Wisconsin's thumb, toward Michigan's Upper Peninsula, or UP. Two distant Michigan cities beyond the horizon leave their  glowing imprint on the darkness of the night sky -- Escanaba, twice as large and twice as close, being much brighter than the dim red glow of Ironwood. The latter is about 30 miles away as the crow flies, while Escanaba is a mere 15, if I'm reading my map right. The dots of red light seem to be channel markers out in the bay.

 What really stands out in spectacular fashion in a dark sky is the Milky Way, that sideways look into the galaxy that the solar system is part of, glowing pale white with the light of billions of stars. Invisible above the lights of a city, in the dark countryside it splashes brightly across the sky, and it's easy to see how it got its name. The photo on the right was taken looking south from Gills Rock, toward the rest of Door County.