The following is an excerpt from space.com:
After a 10-year, 4-billion-mile journey the European Space Agency's Rosetta spacecraft is scheduled to rendezvous with Comet 67P/Churyumov-Gerasimenko on Wednesday (Aug. 6).
The 2.5-mile-wide Comet 67P/Churyumov-Gerasimenko, which takes about 6.5 years to complete one lap around the sun. The comet's elliptical orbit takes it beyond Jupiter at its farthest point from the sun and between Mars and Earth at its closest point.
If all goes according to plan, Rosetta will become the first probe ever to orbit a comet — and, in November, the first to drop a lander onto the surface of one of these icy wanderers.
The Rosetta mission blasted off in March 2004. The probe has swung around the sun five times and zoomed past Earth on three flybys, European Space Agency officials said.
In November, Rosetta drops a lander called Philae onto the surface of the comet. Philae will drill into the comet to take samples and capture images from the surface of the body, ESA officials said.
The observations should reveal a great deal about comet composition, which in turn should help researchers better understand solar system evolution, mission officials have said.