A number of missions have spent time exploring these unknown worlds in the solar system.
In January 2005, the European lander, Huygens stunned the world as it landed on Saturn's largest moon, Titan, revealing unexpected data. Missions such as ESA's SMART-1, which compiled the first comprehensive inventory of key chemical elements in the lunar surface and tested new technology, have become increasingly important today.
To follow-up on the technological breakthroughs of SMART-1, ESA will be participating in Chandrayaan-1, the Indian space agency's lunar mission, due for launch in 2008.

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