It looks like a painting, a 12-foot square field of blue, oddly placed on the ceiling of the simple Quaker meeting room. But this painting is alive, deepening in color and drawing you in as the sun sets outside. It's the sky, you realize. Light artist James Turrell has cut an opening in the roof and tapered its boundaries into a knife-edge that subverts depth perception. It feels as if you could reach up and touch the sky, or that the sky has crept down through the opening to touch you. A bird or a cloud or a plane passing overhead simultaneously breaks the illusion and makes it all the more wonderful.