The glancing rays of the sun, shining almost exactly along the plane of Saturn’s flat rings, draw long shadows from subtle features that bulge out from the plane to a height of up to about 1.5 miles. 

“We never dreamed we’d see things like that,” Porco says. “But there they are. We can’t see these structures when the sun is higher.” 

Astronomers believe large moonlets up to at least a half-mile in size may hide among the rings, which themselves are only about 30 feet thick; the taller vertical structures visible here could be ring material that “splashes” up when the fine particles of the rings collide with these moonlets, much as water at the sea’s edge can splash up and over a rock.