This is the European Space Agency’s Rosetta spacecraft traveling alongside a comet near the orbit of Jupiter. The two bodies are traveling at around 40,000 miles/hour. The comet’s name is 67P/Churyumov-Gerasimenko.
In mid-November, the Rosetta will send a lander named Philae down to the surface of the comet. The two, Rosetta and the comet, will stay locked in orbit for the foreseeable future.
This is Philae
This is the Rosetta
And this is an amazing interactive model of the journey: http://sci.esa.int/where_is_rosetta/