This Galileo lamp series is by Florence-based designer Edoardo Lietti. (As I find is often the case with designers these days, there's virtually no information offered about the design or the thinking behind it.)
"Adjust the shadow simply by rotating the 'planet.'"
The two pivot points of the metal shade appear to ride within a groove inside the circle; it's tough to see as there's no detail shots.
I guess part of the appeal of the object is its DIY aesthetic, but I'd love to see further exploration and refinement.
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