In 2014, the space probe Rosetta began to study the comet 67P/Churyumov-Gerasimenko. In so doing, it also made use of its orbiter spectrometer named Rosina. Rosina had two mass spectrometers and a gas pressure sensor which enabled it to precisely measure the composition of the comet’s atmosphere and ionosphere. Calibration gases from Messer played an indispensable role here: Rosina carried along cylinders containing carbon dioxide, xenon, neon, helium and special gas mixtures. Among the things we learned in the process is that “Chury” truly stinks: It is enveloped by a gas cloud primarily consisting of sulfur dioxide, ammonia and formaldehyde. With its energy reserves running short, Rosetta was intentionally crashed into the comet in 2016.
Gases for Rosina