STAR CLUSTERS PLEASURABLY WORK YOUR BRAIN. As with crossword puzzles, give them time, and satisfying surprises often await. Consider the open cluster Messier 7 in Scorpius (see image on page 38). Certain aspects jump out as soon as you have it in your eyepiece: shape, size, differing magnitudes, how well the cluster stands out from background stars. But dally a bit and you begin to discern subtleties: suns of varying colors, dark dust lanes seemingly weaving between the stars, asterisms you've heard of or invent yourself on the spot.
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