On July 14, 1976 Nancy Holt charted the evolving light and shadow falling to the interior space of one of the cylinders forming her landmark earthwork Sun Tunnels (1973-76). Every half hour, between 6:30 a.m. and 9:00 p.m., she meticulously used her camera to fix the ever-changing rise and set of the sun, bringing together this fifteen hour process into a single composite photograph. Sunlight in Sun Tunnels makes material Holt’s wish to bring the stars down to earth; the perforations in the surface of the tunnel map out star constellations, the holes bringing the sunlight to the ground in an echo of the celestial pattern above.

July 1976 marked the completion of Sun Tunnels and Holt then created this photographic work and Sun Tunnels: Shifting Shadows, joining the body of photo works she made during the research period.