One of the most important science goals of the Rosetta mission is to determine the conditions in the early solar system, as well as the element abundance and climate that led to the development of life on Earth. By studying a comet that has been isolated in Space for 4.5 Billion years, we can learn about the formation of the Solar System and the origin of the raw materials for life on Earth.  The Earth was thought to be so warm when it formed that any water would have evaporated away into space.  If so, where did our vast oceans come...