For most of his life, Bob Miller (1935–2007) was preoccupied with light. He became fascinated by the idea that light is information and set out to explore this subtle proposition. Bob noticed the round spots of sunlight that dapple the ground under a tree on a sunny day, and realized that each spot was an image of the sun, isolated from the sunlight by the gaps between the leaves. Intrigued by the artistic possibilities of these sun images, Bob began experimenting.
In the summer of 1975, he started showing his discoveries about images and sunlight to friends in a series of demonstrations known as Image Walk—then, later, as Light Walk. At the time, he was a young artist building now-iconic sun, prismatic, and reflection exhibits that evoke curiosity and noticing, which are at the core of the Exploratorium experience.
Bob's Light Walk is an Exploratorium institution. It has been nourished by the comments and questions of visitors, interns, teachers, Explainers, and Exploratorium staff. A Light Walk can last an hour, or a day. It begins outside the museum with a single image of the sun, and it ends inside with exhibits on images and shadows. It can lead almost anywhere.