The Darkest Skies
in Montana

"Smoke haze on the western horizon due to wildfires in Idaho, causing elevational extinction coefficients. Night was calm and clear. Computer issues only allowed one set of data to be taken for the night. SQM 21.6"

"High cirrus and poor tranparency, then clearing. M13, M31, and M33 all naked eye."

"Toward Columbia Falls lots of light, bright white glare illuminating the mountains from some sort of industrial yard, at least 10 unshielded lights visible, bright enough to kill night vision, casts shadows. Wonderful sky if you can get away from the glare. Milky Way directly overhead, very bright with much detail in Cygnus, all the rifts and holes apparent, North America nebula an easy visual object. Also in Cassiopeia much detail, bridge in the MIlky Way north of Mirfak visible. Sagittarius Milky Way washed out by Columbia falls area, the light dome of which extends 30 degrees from horizon upward, 40-50 degrees wide."

"The light dome of West Yellowstone (only 1.5 miles to the west) is very prominent and dominates the western horizon. Bozeman is barely visible to the north, likely due to low clouds in the distance."

"Clear night with fair transparency above 20 degrees. Haze visible along the horizon. Seeing fair. Local light from the reservation was direct glare, while the light dome from Hardin was the largest. Billings and Sheridan light domes visible but not bright. Overall the direct glare was distracting, but blocking this allowed for dark adaptation. Milky Way was easily seen with detail in sagittarius, and dust lanes. Visible from tail of Scorpius in South to Cassiopeia. SQM 21.64 at 0130; SQM-L 21.63 at 0152."

"Some direct glare creating difficulties in dark adapting looking north. M13, 31, and 33 all visible naked eye. SQM measure of 21.77"

"Sky quality measurements were recorded at Skyline Vista in Theodore Roosevelt NP on 9/30/2010. The site demonstrated a scientific darkness reading of 21.45 SQM."

"Sky quality measurements were recorded at Oxbow Overlook in Theodore Roosevelt NP on 10/1/2010. The site demonstrated a scientific darkness reading of 21.45 SQM."

"A very faint light dome from Butte (60 miles distant) and nothing apparent from Wisdom, the nearest community (9 miles). Very fine detail visble in the Milky Way, with the Prancing Horse easily seen and the dust lanes in great detail. Stars are visible to the horizon in the south. Saw limiting magnitude star of 7.2 in Draco. Mars and Jupiter very bright to the SE and SW."

"Prancing Horse barely visible. Daytime visibilty slightly impaired by agricultural burning in the Big Horn Valley. The Devil Canyon Overlook is a great spot for observing the night sky or astrophotography. The Horseshoe Bend Campground is even more protected by terrain from the direct glare of Lovell."