Live coverage: Rosetta’s final hours

Europe’s Rosetta spacecraft will close out a historic 4.9-billion-mile journey Friday with a slow-speed crash into the nucleus of comet 67P/Churyumov-Gerasimenko, the tiny world it has studied for the last two years, capturing some of the mission’s best science data to help unravel the inner workings of the comet. Confirmation of the crash landing should arrive on Earth around 1218 BST.


How comets break up and make up

For some comets, breaking up is not that hard to do. A new study indicates that the bodies of some periodic comets — objects that orbit the Sun in less than 200 years — may regularly split in two, then reunite down the road. This may be a repeating process fundamental to comet evolution.

Top Stories 2015

No. 9 Rosetta rides with its comet

While 2014 was the year the Rosetta spacecraft celebrated making it into orbit around a comet, 2015 was the year it got down to some serious hard work. Its comet, with the tongue-twisting name 67P/Churyumov–Gerasimenko, made its closest approach (186 million kilometres) to the Sun, a period known as perihelion when the comet would be expected to be at its most active. Rosetta was there to witness this.


How Rosetta’s comet got its shape

The origin of of Comet 67P/Churyumov-Gerasimenko’s double-lobed form has been a key question since Rosetta first revealed its surprising shape in July 2014. By studying the layers of material seen all over the nucleus, scientists have shown that the shape arose from a low-speed collision between two fully fledged, separately formed comets.