Our target this month is the globular cluster M5 in the constellation Serpens Caput, the head of the celestial serpent. My favorite route to the cluster involves a couple of triangles. Imagine 3.7-magnitude Epsilon (ε) and 3.5-magnitude Mu (μ) Serpentis as two points of an equilateral triangle and M5,8° to the west serving as the third point, completing the shape. I see another triangle: The stars 5,6,and 10 Serpentis form a shape like a pizza slice, with the globular lying just off its northwestern corner. I fancy that M5 is a glittering jewel protected by the serpent rearing to the north.
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