For more than ten years, the European Space Agency's Rosetta spacecraft careened through space in pursuit of the 4km (2.5 miles) wide comet 67P/Churyumov–Gerasimenko, which is moving at nearly 55,000 kilometres (34,000 miles) per hour. Last night, it caught up to its target after travelling 6.4 billion kilometres (3.97 billion miles). Currently just 100km (62 miles) from the comet's surface, Rosetta has been returning close-up images, some of which show a mosaic of craters, boulders, and steep cliffs.

"Our first clear views of the comet have given us plenty to think about," said Rosetta project scientist Matt Taylor in a statement. "Is this double-lobed structure built from two separate comets that came together in the Solar System’s history, or is it one comet that has eroded dramatically and asymmetrically over time?" The next few months will be eventful. Scientists will eventually attempt to have Rosetta orbiting 67P/CG at 30km (about 18 miles), before possibly moving the spacecraft even closer. Most importantly, preparations will take place to lock down another historical first: landing a man-made object on a comet.