By the end 1993, the European Space Agency retained the ROSETTA mission as third "keystone" of its obligatory scientific program "Horizon 2000".

This mission goal is to realize of a rendez-vous with the Churyumov Gerasimenko comet.

The ROSETTA satellite will fly with the comet during a part of its orbit and will enable to study the nucleus as well as its evolution through its approach to the Sun, by remote sensing techniques and by analysis of the ground itself.

The measurements realized will enable a better understanding of :

the nucleus internal structure,
the nucleus nature and the mineralogical, chemical and isotopical composition, notably its organic component,
the interaction between the nucleus and the solar wind or the radiation pressure.

After analysis by the scientific community, those data will be used to progress in the general understanding of comet issues.