Search Publications
On the Abiotic Origin of Dimethyl Sulfide: Discovery of Dimethyl Sulfide in the Interstellar Medium
Caselli, Paola; Martín, Sergio; Jiménez-Serra, Izaskun +14 more
Following the discovery of dimethyl sulfide (DMS; CH3SCH3) signatures in comet 67P/Churyumov–Gerasimenko, we report the first detection of this organosulfur species in the interstellar medium during the exploration of an ultradeep molecular line survey performed toward the Galactic center molecular cloud G+0.693-0.027 with th…
Primordial Origin of Methane on Eris and Makemake Supported by D/H Ratios
Mousis, Olivier; Werlen, Aaron; Benest Couzinou, Tom +1 more
Deuterium, a heavy isotope of hydrogen, is a key tracer of the formation of the solar system. Recent James Webb Space Telescope observations have expanded the data set of deuterium-to-hydrogen (D/H) ratios in methane on the KBOs Eris and Makemake, providing new insights into their origins. This study examines the elevated D/H ratios in methane on …
Boulder Migration in the Khonsu Region of Comet 67P/Churyumov–Gerasimenko
Shi, Xian; El-Maarry, Mohamed Ramy; Tang, Xiang
The European Space Agency's Rosetta mission is the only space mission that has performed long-term monitoring of a comet at close distances. For over two years, Rosetta rendezvoused with comet 67P/Churyumov–Gerasimenko, which revealed diverse evolutionary processes of the cometary nucleus. One of the most striking events is the migration of a ∼30 …
The Ice Chemistry in Comets and Planet-forming Disks: Statistical Comparison of CH3OH, H2CO, and NH3 Abundance Ratios
Ceccarelli, Cecilia; Codella, Claudio; Villanueva, Geronimo L. +5 more
Comets are frozen remnants of our solar system's formation, and comparing their chemical composition to that of planet-forming systems can reveal crucial insights about our origins, potentially answering one of the most challenging questions in planetary science, i.e., whether cometary material was mainly inherited from the protosolar nebula or re…
Diurnal Ejection of Boulder Clusters on Comet 67P Lasting beyond 3 au
Keller, Horst Uwe; Shi, Xian; Güttler, Carsten +6 more
Ejection of large boulder-like debris is a vigorous form of cometary activity that is unlikely induced by water ice out-gassing alone but rather associated with the sublimation of super-volatile ices. Though perceived on several comets, the actual pattern and mechanism of such activity are still unclear. Here we report on a specialized observation…
Evidence for Abiotic Dimethyl Sulfide in Cometary Matter
De Keyser, Johan; Altwegg, Kathrin; Hänni, Nora +5 more
Technological progress related to astronomical observatories such as the recently launched James Webb Space Telescope (JWST) allows searching for signs of life beyond our solar system, namely, in the form of unambiguous biosignature gases in exoplanetary atmospheres. The tentative assignment of a 1σ–2.4σ spectral feature observed with JWST in the …
A Broad Set of Solar and Cosmochemical Data Indicates High C-N-O Abundances for the Solar System
Lunine, Jonathan I.; Glein, Christopher R.; Truong, Ngoc
We examine the role of refractory organics as a major C carrier in the outer protosolar nebula and its implications for the compositions of large Kuiper Belt objects (KBOs) and CI chondrites. By utilizing Rosetta measurements of refractory organics in comet 67P/Churyumov–Gerasimenko, we show that they would make up a large fraction of the protosol…
Interaction between a Coronal Mass Ejection and Comet 67P/Churyumov–Gerasimenko
Gombosi, Tamas I.; Combi, Michael R.; Altwegg, Kathrin +6 more
The interaction between a coronal mass ejection (CME) and a comet has been observed several times by in situ observations from the Rosetta Plasma Consortium, which is designed to investigate the cometary magnetosphere of comet 67P/Churyumov–Gerasimenko (CG). Goetz et al. reported a magnetic field of up to 300 nT measured in the inner coma, which i…
Spacecraft Charging Simulations of Probe B1 of Comet Interceptor during the Cometary Flyby
Henri, P.; Miyake, Y.; Johansson, F. L. +2 more
Comet Interceptor will be the first mission to make a flyby of a long-period or interstellar comet. After launch, the spacecraft will wait at the Sun-Earth Lagrange point L2 for a yet-to-be-discovered comet to appear. The mission comprises three spacecraft: One main spacecraft, A, developed by ESA, and two subprobes, B1 and B2, developed by JAXA a…
Effects of Grain Alignment with Magnetic Fields on Grain Growth and the Structure of Dust Aggregates
Hoang, Thiem
Dust grains drift through the interstellar medium and are aligned with the magnetic field. Here we study the effect of grain alignment and motion on grain growth in molecular clouds (MCs). We first discuss the characteristic timescales of alignment of the grain axis of maximum inertia ( $\hat{{\boldsymbol{a}}}$ 1) with its angular momen…