Atolls are tantalizing in their size, shape, and isolation. The tiny ring-shaped islands formed by build up of coral from previous volcanic islands evoke the desert islands of our dreams: lonely stretches of sand in the middle of crystal clear waters, with few if any people around.
Satellite images and photos taken by astronauts aboard the International Space Station accentuate what makes them so beautiful—thin wisps of coral and sand encasing deep blue lagoons.