Rosetta is scheduled to be launched on board an Ariane-5 rocket on 26 February from Kourou, French Guiana.
This will be the first mission to orbit and land on a comet Churyumov-Gerasimenko, one of the icy bodies that travel throughout the Solar System and develop a characteristic tail when they approach the Sun.
Comets are very interesting objects for scientists, since their composition reflects how the Solar System was when it was very young and still 'unfinished', more than 4600 million years ago. Comets have not changed much since then. So Rosetta will collect information essential to an understanding of the origin and evolution of our Solar System. It will also help discover whether comets contributed to the beginnings of life on Earth. Comets are carriers of complex organic molecules that, delivered to Earth through impacts, perhaps played a role in the origin of living forms. Furthermore, volatile light elements carried by comets might also have played an important role in forming the Earth's oceans and atmosphere.
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