Laboratory experiments for the interpretation of mass spectra from water ice particles measured in-situ onboard Cassini and future space missions
Final Report Abstract
Most of the dust in the outer solar system is made of water ice with embedded other components. In-situ instruments onboard interplanetary spacecrafts perform TOF mass spectrometry of hypervelocity micro-particle impacts. The interpretation of these spectra strongly relies on laboratory data. We have performed a large set of laboratory experiments in order to unravel space data. We have also investigated fundamental mechanisms of charge separation, relevant for the velocity dependent detection process. Although, the IR-laser impact on a microbeam in vacuum (in the laboratory) has been found to be a good analogue for the impact of ice grains on detector electrodes in space resulting in decomposition and charge, as well as ion formation, it is not perfect. Therefore, a prototype ice particle accelerator has been tested and characterized. An advanced version of the laser driven ice particle accelerator is in progress at present. The ice particles are generated and accelerated by laser dispersion of a micro beam and the charged particles will be discriminated by electric fields. This will bring the laboratory experiments even closer to the space measurements in the future. One encouraging very recent discovery by the Cosmic Dust Analyzer (CDA) of Cassini and complementing laboratory experiments is the presence of complex organic macromolecular compounds in a subset of the plume ice grains. As the detection of these organics is dependent on impact speed, it is likely that they are fragments of larger organic molecules outside of the CDA mass range. So, the ocean of Enceladus may have the appropriate chemical inventory to enable life to subsist or originate.
Publications
- (2019) Analogue spectra for impact ionization mass spectra of water ice grains obtained at different impact speeds in space. Rapid communications in mass spectrometry : RCM 33 (22) 1751–1760
Klenner, Fabian; Postberg, Frank; Hillier, Jon; Khawaja, Nozair; Reviol, René; Srama, Ralf; Abel, Bernd; Stolz, Ferdinand; Kempf, Sascha
(See online at https://doi.org/10.1002/rcm.8518) - (2020) Analog Experiments for the Identification of Trace Biosignatures in Ice Grains from Extraterrestrial Ocean Worlds. Astrobiology 20 (2) 179–189
Klenner, Fabian; Postberg, Frank; Hillier, Jon; Khawaja, Nozair; Reviol, René; Stolz, Ferdinand; Cable, Morgan L.; Abel, Bernd; Nölle, Lenz
(See online at https://doi.org/10.1089/ast.2019.2065) - Linear high resolution dust mass spectrometer for a mission to the Galilean satellites. Planet. Space. Sci. 2012, 65, 10-20
Kempf, S.; Srama, R.; Grun, E.; Mocker, A.; Postberg, F.; Hillier, J. K.; Horanyi, M.; Sternovsky, Z.; Abel, B.; Beinsen, A.; Thissen, R.; Schmidt, J.; Spahn, F.; Altobelli, N.
(See online at https://doi.org/10.1016/j.pss.2011.12.019) - Charge Separation and Isolation in Strong Water Droplet Impacts, Phys. Chem. Chem. Phys., 2015, 17, 6858-6864
F. Wiederschein, E. Vöhringer-Martinez, A. Beinsen, F. Postberg, J. Schmidt, R. Srama, F. Stolz, H. Grubmüller, and B. Abel
(See online at https://doi.org/10.1039/c4cp05618c) - Ongoing hydrothermal activities within Enceladus. Nature 519, 207–210 (2015)
Hsiang-Wen Hsu, Frank Postberg, Yasuhito Sekine, Takazo Shibuya, Sascha Kempf, Mihály Horányi, Antal Juhász, Nicolas Altobelli, Katsuhiko Suzuki, Yuka Masaki, Tatsu Kuwatani, Shogo Tachibana, Sin-iti Sirono, Georg Moragas-Klostermeyer & Ralf Srama
(See online at https://doi.org/10.1038/nature14262) - Explorer of Enceladus and Titan (E2T): Investigating ocean worlds' evolution and habitability in the solar system. Planetary and Space Science 2018, 155, 73-90
Mitri, G.; Postberg, F.; Soderblom, J. M.; Wurz, P.; Tortora, P.; Abel, B.; Barnes, J. W.; Berga, M.; Carrasco, N.; Coustenis, A.; Paul de Vera, J. P.; D'Ottavio, A.; Ferri, F.; Hayes, A. G.; Hayne, P. O.; Hillier, J. K.; Kempf, S.; Lebreton, J.-P.; Lorenz, R. D.; Martelli, A.; Orosei, R.; Petropoulos, A. E.; Reh, K.; Schmidt, J.; Sotin, C.; Srama, R.; Tobie, G.; Vorburger, A.; Vuitton, V.; Wong, A.; Zannoni, M.
(See online at https://doi.org/10.1016/j.pss.2017.11.001) - Macromolecular organic compounds from the depths of Enceladus, Nature 2018, 558, 564-568
Frank Postberg, Nozair Khawaja, Bernd Abel, Gael Choblet, Christopher R. Glein, Murthy S. Gudipati, Bryana L. Henderson, Hsiang-Wen Hsu, Sascha Kempf, Fabian Klenner, Georg Moragas-Klostermeyer, Brian Magee, Lenz Nölle, Mark Perry, René Reviol, Jürgen Schmidt, Ralf Srama, Ferdinand Stolz, Gabriel Tobie, Mario Trieloff & J. Hunter Waite
(See online at https://doi.org/10.1038/s41586-018-0246-4)
