In the October 2012 Sky & Telescope

Binoculars are wonderfully portable and useful instruments for backyard astronomy. And they’re often more capable than the average deep-sky observer suspects. In my feature article, The Messier Catalog: A Binocular Odyssey, I describe using binos to track down all 109 Messier objects as a fun way to sharpen your observing skills and enhance your enjoyment.

Is a fan really the only way to cool your telescope’s mirror? Among those who wondered this is ATM James Stilburn, who performed some careful experiments to discover if a heat sink might be another solution. The results of Jim’s efforts are described in my Telescope Workshop column.

If you want to see what extreme depth of field looks like, train your binoculars on NGC 6939 and 6946, situated near the Cepheus/Cygnus border. This galaxy and cluster duo is the subject of October's Binocular Highlights column.