The European Space Agency probe Rosetta is on its way to comet 67/P Churyumov-Gerasimenko (by way of asteroid 21 Lutetia next July), where it will arrive in May of 2014. It will be dropping a lander -- the first ever attempted on a comet -- and our knowledge of these fuzzy visitors will increase enormously.
But getting there is tough, and involves swinging by the Earth three times and Mars once. The final gravity assist will occur on November 13, with closest approach at 08:45 CET (over, roughly, the island of Java) when it'll be moving past us at 13.3 km/sec (almost 30,000 mph). While it's passing us by it will observe both the Earth and Moon, doing as much science as it can before heading out into deep space. Specifically, it will add its sensors to those already studying water on the Moon, as well as aurorae on Earth.
You can follow the action on the Rosetta blog. In fact, just the other day they posted this awesome shot of the Moon from Rosetta:
That was taken form a distance of 4.3 million kilometers (2.5 million miles), ten times the distance of the Moon from the Earth. The images as it gets closer will be even cooler.
So stay tuned! This is a very exciting mission, especially next year when it passes Lutetia! I can never see enough closeup pictures of asteroids.
Spacecraft image credit: ESA, image by AOES Medialab