On Aug. 6, the European Space Agency’s Rosetta spacecraft went where no man, or probe, had gone before: into orbit around a comet. The rendezvous marked the end of a 4 billion-mile journey and the start of a 17-month orbital mission designed to understand the changes comets undergo as they approach the sun.
Because comets contain material from when the sun and planets formed, Rosetta can answer questions about the evolution of the solar system and the origin of water (and possibly life) on Earth.
Just weeks after arriving near Comet 67P/Churyumov-Gerasimenko, Rosetta delivered the sharpest-ever views of a nucleus — the frozen mass of rock and ice at a comet’s heart. The spacecraft’s camera revealed it as a double-lobed object that some mission scientists referred to as a “rubber ducky,” complete with a head, neck and body. Pocked with craters and littered with boulders, the nucleus measures about 2.5 miles across at its widest.