Rosetta is "the sexiest space mission there's ever been," according to one of the European Space Agency's scientists.
"The science is shaping up wonderfully," Rosetta project scientist Matt Taylor said.
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The Facebook founder revealed the plan as he and wife Priscilla Chan announced the birth of their baby daughter, Max.
At least 300 people are actively promoting and recruiting for the terror group from within the United States, academics have found.
Hollywood film director and actor Steven Seagal has been asked to train Serbian special forces in martial arts.