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Lunar limb magic

Explore often-overlooked features of the Moon’s edge.
OMearaStephen
he Moon, the brightest object in the night sky, has a naked-eye secret: its limb. The illuminated edge of the Moon’s visible surface has a remarkable nature that’s easy to overlook. What you experience, however, depends on how carefully you examine it.

Note: When I write, “illuminated edge,” I’m not talking about the bright side of the terminator (the line dividing day and night, where shadows highlight the view). I’m referring to the rounded bright edge of the Moon that’s not the terminator. At Full Moon, the illuminated edge goes all the way around.

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