Beth, A.; Altwegg, Kathrin; Balsiger, Hans; Berthelier, J.-J.; Combi, M. R.; De Keyser, J.; Fiethe, B.; Fuselier, S. A.; Galand, M.; Gombosi, T. I.; Rubin, Martin; Sémon, Thierry (2020). ROSINA ion zoo at Comet 67P. Astronomy and astrophysics, 642, A27. EDP Sciences 10.1051/0004-6361/201936775
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Context. The Rosetta spacecraft escorted Comet 67P/Churyumov-Gerasimenko for 2 yr along its journey through the Solar System between 3.8 and 1.24 au. Thanks to the high resolution mass spectrometer on board Rosetta, the detailed ion composition within a coma has been accurately assessed in situ for the very first time.
Aims. Previous cometary missions, such as Giotto, did not have the instrumental capabilities to identify the exact nature of the plasma in a coma because the mass resolution of the spectrometers onboard was too low to separate ion species with similar masses. In contrast, the Double Focusing Mass Spectrometer (DFMS), part of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis on board Rosetta (ROSINA), with its high mass resolution mode, outperformed all of them, revealing the diversity of cometary ions.
Methods. We calibrated and analysed the set of spectra acquired by DFMS in ion mode from October 2014 to April 2016. In particular, we focused on the range from 13–39 u q−1. The high mass resolution of DFMS allows for accurate identifications of ions with quasi-similar masses, separating 13C+ from CH+, for instance.
Results. We confirm the presence in situ of predicted cations at comets, such as CHm+ (m = 1−4), HnO+ (n = 1−3), O+, Na+, and several ionised and protonated molecules. Prior to Rosetta, only a fraction of them had been confirmed from Earth-based observations. In addition, we report for the first time the unambiguous presence of a molecular dication in the gas envelope of a Solar System body, namely CO2++.
Item Type: |
Journal Article (Original Article) |
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Division/Institute: |
08 Faculty of Science > Physics Institute > Space Research and Planetary Sciences 08 Faculty of Science > Other Institutions > Emeriti, Faculty of Science 08 Faculty of Science > Physics Institute |
UniBE Contributor: |
Altwegg, Kathrin, Balsiger, Hans, Rubin, Martin, Sémon, Thierry |
Subjects: |
500 Science > 520 Astronomy 600 Technology > 620 Engineering 500 Science > 530 Physics |
ISSN: |
0004-6361 |
Publisher: |
EDP Sciences |
Language: |
English |
Submitter: |
Dora Ursula Zimmerer |
Date Deposited: |
03 Nov 2020 10:43 |
Last Modified: |
05 Dec 2022 15:41 |
Publisher DOI: |
10.1051/0004-6361/201936775 |
BORIS DOI: |
10.7892/boris.147325 |
URI: |
https://boris.unibe.ch/id/eprint/147325 |