This image shows the spectacular “diamond ring” that appears during a total solar eclipse. Surprisingly, the ring is caused by mountains on the Moon. During a solar eclipse, the Moon comes between the Earth and the Sun and gradually cuts off the Sun’s light. Just before the Moon eclipses the Sun completely, light shines through the irregular mountains on the Moon’s edge, which break the last crescent of the light into tiny beadlike patterns known as Bailey’s Beads. The last of the beads shines brighter than the Sun’s other visible features and creates the “diamond”; the Sun’s corona forms the “ring.”