July 3, 2008—Rosetta, a European Space Agency spacecraft launched in 2004, passes an asteroid in an artist's conception.

Mission controllers announced last Thursday that they woke Rosetta from a three-month hibernation to prepare the probe for its September rendezvous with asteroid (2867) Steins. ESA scientists hope to learn more about the space rock, such as its physical and chemical properties.

The asteroid flyby will also give Rosetta's controllers a chance to test the craft's instruments as it continues on its mission to land on comet 67/P Churyumov-Gerasimenko. The probe is expected to reach its final destination in 2014, having traveled about 4,040 million miles (6,500 million kilometers).

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