Search Publications
High D/H ratios in water and alkanes in comet 67P/Churyumov-Gerasimenko measured with Rosetta/ROSINA DFMS
Altwegg, K.; Berthelier, J. J.; Fuselier, S. A. +8 more
Context. Isotopic abundances in comets are key to understanding and reconstructing the history and origin of material in the Solar System. Data for deuterium-to-hydrogen (D/H) ratios in water are available for several comets. However, no long-term studies of the D/H ratio in water of a comet during its passage around the Sun have been reported thu…
Successive deuteration in low-mass star-forming regions: The case of D2-methanol (CHD2OH) in IRAS 16293-2422
Margulès, Laurent; Drozdovskaya, Maria N.; Jørgensen, Jes K. +3 more
Context. Di-deuterated molecules are observed in the earliest stages of star formation at abundances of a few percent relative to their nondeuterated isotopologs, which is unexpected considering the scarcity of deuterium in the interstellar medium. With sensitive observations leading to the detection of a steadily increasing number of di-deuterate…
VLT spectropolarimetry of comet 67P: dust environment around the end of its intense southern summer
Kolokolova, Ludmilla; Agarwal, Jessica; Snodgrass, Colin +5 more
Context. A cornucopia of Rosetta and ground-based observational data sheds light on the evolution of the characteristics of dust particles from comet 67P/Churyumov-Gerasimenko (hereafter 67P) with seasons, implying the different dust environments in the source regions on the surface of the comet.
Aims: We aim to constrain the properties of th…
Upstream solar wind speed at comet 67P. Reconstruction method, model comparison, and results
Holmström, M.; Gunell, H.; Futaana, Y. +7 more
Context. Rosetta followed comet 67P at heliocentric distances from 1.25 to 3.6 au. The solar wind was observed for much of this time, but was significantly deflected and to some extent slowed down by the interaction with the coma.
Aims: We use the different changes in the speed of H+ and He2+ when they interact with the …
Quantification of O2 formation during UV photolysis of water ice: H2O and H2O:CO2 ices
Linnartz, H.; Chuang, K. -J.; Fedoseev, G. +4 more
Context. The Rosetta and Giotto missions investigated the composition of the cometary comae of 67P/Churyumov-Gerasimenko and 1P/Halley, respectively. In both cases, a surprisingly large amount of molecular oxygen (O2) was detected and was well correlated with the observed abundances of H2O. Laboratory experiments simulating c…
Development of a cometosheath at comet 67P/Churyumov-Gerasimenko. A case study comparison of Rosetta observations
Nilsson, H.; Goetz, C.; Stenberg Wieser, G. +2 more
Context. The ionosphere of a comet is known to deflect the solar wind through mass loading, but the interaction is dependent on cometary activity. We investigate the details of this process at comet 67P using the Rosetta Ion Composition Analyzer.
Aims: This study aims to compare the interaction of the solar wind and cometary ions during two d…
On the trail of a comet's tail: A particle tracking algorithm for comet 67P/Churyumov-Gerasimenko
Agarwal, Jessica; Pfeifer, Marius; Schröter, Matthias
Context. During the post-perihelion phase of the European Space Agency's Rosetta mission to comet
Radial distribution of plasma at comet 67P. Implications for cometary flyby missions
Henri, P.; Edberg, N. J. T.; Vigren, E. +3 more
Context. The Rosetta spacecraft followed comet 67P/Churyumov-Gerasimenko (67P) for more than two years at a slow walking pace (~1 m s−1) within 1500 km from the nucleus. During one of the radial movements of the spacecraft in the early phase of the mission, the radial distribution of the plasma density could be estimated, and the ionosp…
Probing the surface environment of large T-type asteroids
Hasegawa, Sunao; Agarwal, Jessica; Fornasier, Sonia +2 more
Context. The thermal and radiative environments encountered by asteroids have shaped their surface features. Recent observations have focused on asteroids in the main belt and showed indications for ices and organics in the interiors of the asteroids that were likely significant on prebiotic Earth. They stand out in reflectance spectra as darker, …
Water ortho-to-para ratio in the coma of comet 67P/Churyumov-Gerasimenko
Encrenaz, T.; Erard, S.; Crovisier, J. +9 more
Context. Abundance ratios of the nuclear-spin isomers of H2O and NH3 have been measured in about two dozen comets, with a mean value corresponding to a nuclear-spin temperature of ~30 K. The real meaning of these unequilibrated nuclear-spin abundance ratios is still debated. However, an equilibrated water ortho-to-para ratio …