Our target this month is M71,an 8.4-magnitude gablobular cluster in Sagitta, the Arrow, hanging halfway between Delta (δ) and Gamma (γ) Sagittae. More than any other celestial object, M71 taught me how to observe. Early on, I struggled to find the cluster at all, despite using a 6-inch reflector. Now I check in on it regularly - and more often than not, I'm only using binoculars. So, what changed? In the old days I'd haul out the scope, paying minimal attention to local conditions or where things were situated in the sky, then start running up the magnification. That was exactly the wrong strategy for M71. The cluster is so loosely aggregated that for a long time astronomers suspected it to be a dense open cluster rather than a globular. To make matters worse, M71 sits in a dense stretch of the Milky Way. High magnification restricts the field of view so much that the cluster starts to blend into the rich galactic background, especially in poor skies.
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