This is a clock on display at the Metropolitan Museum of Art.
I've seen this piece before, and have another photograph of it somewhere, but it was only with this shot that I realized that the piece is meant to be seen from this angle. Or maybe I should say this the the side of the clock that is the art and imagination side. The other (top) side has the dials and markings that allow you to tell the time and (probably) the seasons.
I like this because it's a clock, and astrolabe all rolled up into one. I like it because it's (mostly) silver. And I like it because Pegasus - unlike the Sisyphusian Atlases holding up other globe clocks - looks like flying with the heavens on his back isn't any trouble at all.