Bob Miller/Light Walk

Core Lesson Idea: Exploring the idea that light is information by using a collection of simple, everyday props and tools.

Artistic Process: Bob Miller was both a teacher and student of light. Inspired by casual observations made in his everyday wanderings in sun and shadow, in 1975 Miller developed his now-famous Light Walks, pedagogical walking tours that illuminated fundamental truths about how lights works, what it's made of, and how we perceive it.

“It begins here, with a commonly observed and reported phenomenon: the light coming through the cracks between the leaves in the trees hits the ground or a piece of white cardboard and is round. Now you know that the spaces between the leaves aren't round. They're all irregular. The round spots of light are images of the sun.

“One thing that occurred to me when I looked at this was that there must also be an image of the sky surrounding the sun. The light from the sky must get through the holes, too. But we aren't normally aware of it, because the blue light of the sky is so dim compared to the sun. The sun is really bright—about a million times brighter than the moon. And the moon is even brighter than the clear blue sky. Now it turns out that sometimes by chance, if the sun is partially covered or surrounded by scuddy clouds or fog, then around each one of these sun images, you actually see the clouds going by.

"The reason the sun shows up so well is that the sun is so bright. But actually, each hole also lets through a complete image of whatever is on the other side, including the sky, the houses, the people.”  

© Exploratorium, photo: Nancy Roger, 1987

Historical Context: Bob Miller’s creative practice was defined by an "unhardening of the categories," as he used to say—a refusal to accept formal categories of study such as science, art, math, or engineering. Instead, he called himself a "natural philosopher" and made a practice of wandering, musing, hypothesizing, and collaborating, building new questions on the backs of the old ones.

Miller was born in Niagara Falls and studied at Hiram College in Ohio. After working for a short time with the army at the White Sands Proving Ground in New Mexico, he began computer programming at IBM, later joining the United States Merchant Marine and eventually settling in San Francisco. Fascinated by optics, he began to construct artful experiments using natural light and prisms in his small apartment.

During a 1970 visit from Exploratorium Founding Director Frank Oppenheimer, Miller was offered a job at the Exploratorium that lasted nearly 20 years. His early investigations gave way to the creation of the museum’s Artist-in-Residence program, and he played several roles on staff, including exhibit developer, teacher, and assistant director of the museum. He designed and built a number of beloved and iconic exhibits at the Exploratorium that explored light, color, shadow, and perception, including: Sun Painting (1970), Sophisticated Shadows (1980), Cheshire Cat (1978), Everyone Is You and Me (1980), and Aurora (1976).

Perhaps his most enduring contribution was the most ephemeral: Miller’s Light Walk was a pedagogical walking tour that lasted from an hour to an entire day, illuminating principles of light using simple yet ingenious props and tools. Those lucky enough to experience a Walk never see the world around them in quite the same way.

Keywords: color, environment, geometry, light, optics, pattern, perception, natural phenomena, walking

Lesson: Light Walk