For centuries astronomers have chased comets across the skies, looking for clues as to the origins of our solar system. Tugged from deep-space by the gravity of the sun, they shed dust and gas as they warm, revealing some of their secrets within.
Beguiling and bewildering in equal measure these celestial visitors continue to hold the fascination of today's stargazers.
In this edition of Space we talk to some top European scientists striving to unravel the mysteries of comets.
As a starting point Hermann Böhnhardt, Senior Research Scientist, at the Max Planck Institute for Solar System Research put comets into perspective: "A comet is a piece of rock and ice, mixed together, roughly to imagine, something like Mont Blanc, or one of the larger mountains in the Alps - that is the size of a comet."
Frozen within this rocky mass are secrets about our own origins, according to Gerhard Schwehm, Cometary Scientist at the European Space Agency:
"Comets are interesting for a lot of reasons and one reason we are looking- and it's the most fascinating reason- is 'have comets played a role to bring life onto Earth'?"
