Video: Mission control celebrates separation but anxiety builds over landing

If it were possible to breath in space, one would smell a pungent aroma of rotten eggs, ammonia, vinegary sulphur dioxide and toxic hydrogen cyanide coming from comet 67P/Churyumov–Gerasimenko, according to sensors on the Rosetta mission.

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.

Research teams across Europe spent the last half-year meticulously going through a wish list of experiments for the Philae comet lander without knowing whether they would ever get a chance to execute the tasks.