In the 17th century, astronomers Christiaan Huygens and Giovanni Cassini trained their telescopes on Saturn and uncovered a startling truth: the planet's luminous bands were not solid appendages, but vast,

The small moon is one of 274 orbiting Saturn and has long been considered a prime candidate in the search for life beyond Earth because of its hidden ocean and plumes of water erupting from cracks near its south pole.

Scientists believe life may exist in Enceladus' subsurface ocean. Now, a new ESA mission will send spacecraft to the moon to probe for life.