Search Publications
Cyanogen, cyanoacetylene, and acetonitrile in comet 67P and their relation to the cyano radical
Altwegg, K.; Balsiger, H.; Fuselier, S. A. +6 more
The cyano radical (CN) is one of the most frequently remotely observed species in space, and is also often observed in comets. Data for the inner coma of comet 67P/Churyumov-Gerasimenko collected by the high-resolution Double Focusing Mass Spectrometer (DFMS) on board the Rosetta orbiter revealed an unexpected chemical complexity, and, recently, a…
Plasma densities, flow, and solar EUV flux at comet 67P. A cross-calibration approach
Nilsson, H.; Henri, P.; Edberg, N. J. T. +7 more
Context. During its two-year mission at comet 67P, Rosetta nearly continuously monitored the inner coma plasma environment for gas production rates varying over three orders of magnitude, at distances to the nucleus ranging from a few to a few hundred kilometres. To achieve the best possible measurements, cross-calibration of the plasma instrument…
Multi-instrument analysis of far-ultraviolet aurora in the southern hemisphere of comet 67P/Churyumov-Gerasimenko
Feldman, P. D.; Eriksson, A.; Biver, N. +9 more
Aims: We aim to determine whether dissociative excitation of cometary neutrals by electron impact is the major source of far-ultraviolet (FUV) emissions at comet 67P/Churyumov-Gerasimenko in the southern hemisphere at large heliocentric distances, both during quiet conditions and impacts of corotating interaction regions observed in the summe…
Small lobe of comet 67P: Characterization of the Wosret region with ROSETTA-OSIRIS
Sierks, H.; Barucci, M. A.; Fornasier, S. +3 more
Aims: We investigated Wosret, a region located on the small lobe of the 67P/Churyumov-Gerasimenko comet subject to strong heating during the perihelion passage. This region includes the two last landing sites of the Philae lander as well as, notably the final one, Abydos, where the lander performed most of its measurements. We study Wosret in…
Detection of volatiles undergoing sublimation from 67P/Churyumov-Gerasimenko coma particles using ROSINA/COPS. I. The ram gauge
Altwegg, K.; Balsiger, H.; Rubin, M. +5 more
Context. The ESA Rosetta mission has allowed for an extensive in situ study of the comet 67P/Churyumov-Gerasimenko. In measurements performed by the ram gauge of the COmet Pressure Sensor (COPS), observed features are seen to deviate from the nominal ram gauge signal. This effect is attributable to the sublimation of the volatile fraction of comet…
Galactic cosmic ray modulation at Mars and beyond measured with EDACs on Mars Express and Rosetta
Johnstone, A.; Lester, M.; Wimmer-Schweingruber, R. F. +5 more
Galactic cosmic rays (GCRs) are an intrinsic part of the heliospheric radiation environment and an inevitable challenge to long-term space exploration. Here we show solar-cycle-induced GCR modulation at Mars in the period 2005-2020, along with GCR radial gradients, by comparing Mars Express and Rosetta engineering parameters to sunspot number time…
The effect of thermal conductivity on the outgassing and local gas dynamics from cometary nuclei
Thomas, N.; Marschall, R.; Gerig, S. -B. +3 more
Aims: The aim of this work is to investigate the parameters influencing the generation of the inner comae of a comet with a spherical nucleus and to model the gas activity distribution around its nuclei. Here, we investigate the influence of thermal conductivity combined with sub-surface H2O and CO2-ice sources on insola…
Electric field measurements at the plasma frequency around comet 67P by RPC-MIP on board Rosetta
Palmerio, E.; Nilsson, H.; Henri, P. +7 more
Context. The Mutual Impedance Probe (RPC-MIP) carried by the Rosetta spacecraft monitored both the plasma density and the electric field in the close environment of comet 67P/Churyumov-Gerasimenko (67P), as the instrument was operating alternatively in two main modes: active and passive. The active mode is used primarily to perform plasma density …
Gas terminal velocity from MIRO/Rosetta data using neural network approach
Hartogh, P.; Crovisier, J.; Ip, W. H. +8 more
Context. The Microwave Instrument on the Rosetta Orbiter (MIRO) on board the Rosetta spacecraft was designed to investigate the surface and gas activity of the comet 67P/Churyumov-Gerasimenko. The MIRO spectroscopic measurements carry information about the velocity of gas emanating from the nucleus surface. Knowledge of the terminal velocity of th…
Ancient and present surface evolution processes in the Ash region of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Groussin, O.; Bouley, S. +3 more
Aims: The Rosetta mission provided us with detailed data of the surface of the nucleus of comet 67P/Churyumov-Gerasimenko. In order to better understand the physical processes associated with the comet activity and the surface evolution of its nucleus, we performed a detailed comparative morphometrical analysis of two depressions located in t…