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Rosetta lessons

The Rosetta spacecraft which is en route to a comet in 2014 also watched the event.

"One of the big unknowns is the internal structure of the nucleus, how it sticks together and the strength of the material," said Rosetta project scientist Dr Gerhard Schwehm.

"These are things we hope to learn now from the science of Deep Impact."


�In pictures:�Deep Impact: A mission to crash into a comet

	Rosetta lessons The Rosetta spacecraft which is en route to a comet in 2014 also watched the event. "One of the big unknowns is the internal structure of the nucleus, how it sticks together and the strength of the material," said Rosetta project scientist Dr Gerhard Schwehm. "These are things we hope to learn now from the science of Deep Impact."