MODEL RELEASED. Eclipse viewing sunglasses. Woman wearing glasses designed to protect her eyes while watching a total eclipse of the Sun. The lenses reduce the sunlight's intensity, making it safe to view the Sun for short periods. Solar eclipses occur when the Moon passes between the Earth and the Sun, casting a shadow across the Earth. View- ing the Sun directly can cause blindness. Photo- graphed in Cornwall, England, on August 11 1999.