Total solar eclipse. Baily's beads seen at the edge of the Moon's disc during a total solar eclipse. The beads (lower right) form just before (and just after) totality, when the last visible crescent of the Sun's face is broken up by valleys and mountains on the Moon's limb. Solar eclipses occur when the Moon passes between the Earth and the Sun. This was the 11th August 1999 eclipse. Photographed from Turkey.