Stars circle the north pole as the earth turns in this fixed-tripod exposure from a dark site. The brightest two trails above center on the left are from the two stars that form the front of the "pan" of the "Little Dipper". Polaris, the North Star, is to the right of center near the middle of the circles. The colors of the trails generally reflect the stars' surface temperatures or their composition. For example, the red trail on the upper left edge of the rightmost tree is from a carbon star, an aging star whose atmosphere contains more carbon than oxygen. Carbon compounds that form in the star tint the star ruby red.

177 30-second exposures with a Canon 40D 17mm at f4 spanning 96 minutes on 2012-08-18 from near Speculator, NY. ©2013

Stars circle the north pole as the earth turns in this fixed-tripod exposure taken from my home in northern New Jersey. The brightest two trails in the upper left are from the two stars that form the front of the "pan" of the "Little Dipper". Polaris, the North Star, is below center near the middle of the circles.

219 30-second exposures with a Canon 40D 17mm at f2.8 spanning 2 hours starting at 10:38 p.m. EDT on 2008-07-02 from northern New Jersey. ©2008