Weylin Ryan measures the sky in Durango. Photo: Ziyi Xu, Rocky Mountain PBS DURANGO, Colo. — At 10:18 p.m., Weylin Ryan, a board member of DarkSky Colorado, stood at the intersection of Eighth Street and Second Avenue in downtown Durango. He pointed a sky quality meter toward the cloudless sky. After a quick beep, the device displayed a reading: 19.44 magnitudes per square arcsecond.