... trace their heritage to the interstellar medium from which the protosolar nebula eventually emerged. The most recent cometary space mission, Rosetta , carried instruments designed to characterize, in unprecedented detail, the organic species in comet 67P/Churyumov–Gerasimenko (67P). Rosetta...

... ). The Rosetta mission also observed strong dichotomies in the relative ratios of CO 2 /H 2 O between the northern and southern hemispheres of comet 67P/Churyumov–Gerasimenko, as well as changing mixing ratios of less abundant molecules, as seen from in situ near-IR measurements ( Hässig et al. 2015 ). However...

...Figure 7.2 Exploration of comet 67P/Churyumov-Gerasimenko by the ESA-NASA Rosetta probe. (a) 67P/G-C upon arrival. (b) Artist’s view of the Rosetta spacecraft, with insert showing the double focusing mass spectrometer (DFMS) of the ROSINA instrument that analysed volatiles released...

... to 0.035 ( Yabuta et al. 2023 ) and are within the range of N/C ratios of IOM in carbonaceous chondrites and those of organic particles from comet 67P/Churyumov–Gerasimenko (e.g., Yabuta et al. 2017 ; Fray et al. 2017 ; F ig . 4 ). Organic matter from particles from comet 81P/Wild2, interplanetary dust...

...F igure 5 An agglomerate dust particle from comet 67P/Churyumov–Gerasimenko, as collected by COSIMA (cometary secondary ion mass analyzer). The image was obtained using grazing illumination from the right. The length of the shadows indicates that the altitude above the substrate reaches about...

... by spacecraft. Prior to the investigation of comet 67P/Churyumov–Gerasimenko by the European Space Agency's Rosetta mission (Grady et al. 2018 this issue), there had been close encounters with six other comets ( Fig. 1 ). Rosetta included both a rendezvous spacecraft for extended measurements near...

... organic molecules in the icy particles of a protoplanetary disk were detected using NASA’s newly launched James Webb Space Telescope (JWST) ( Yang et al. 2022 ). Previously, the Rosetta space mission detected large organic molecules in the dust particles of comet Churyumov–Gerasimenko (67P/CG), which...

..., have been detected in comets ( Biver and Bockelée-Morvan 2019 ). In-situ space missions, such as the Rosetta mission to comet 67P/Churyumov–Gerasimenko have further identified more than 60 individual organic molecules ( Altwegg et al. 2017 ), including glycine, alcohols, carbonyls, amines, nitriles...

.... Comets and their meteoroids have a low density. Matter must have assembled with low relative speed to create the contact-binary and onion-shell morphology of comet 67P/Churyumov–Gerasimenko, observed in close proximity by the Rosetta mission (see Grady et al. 2018 this issue). Once they had formed...

... imagination in a way little else can. Who could not be enthralled by the evocatively named Stardust mission returning a few thousand grains of dust from comet Wild 2 to Earth? We collectively shared the despair when communication was lost from Rosetta 's Philae lander on comet 67P/Churyumov–Gerasimenko...

... orders of magnitude (see Fig. 2 ). In the latest giant step, the Rosetta spacecraft orbited, and deposited a probe on comet 67P/Churyumov–Gerasimenko, as described by Grady et al. (2018 this issue). In many ways, we live at the perfect time to be “cometologists”. However, the mission that most...

... that can be seen from orbit; these patterns have been reported on Venus, Earth, Mars, Titan, Io, Pluto, and the 67P/Churyumov-Gerasimenko comet ( Fig. 1 ; Bourke et al., 2010 ; Thomas et al., 2015 ; Telfer et al., 2018 ; McDonald et al., 2022 ). Because dunes and their patterns form and evolve...