Speaker
Description
The elemental composition In our early solar system is still one of the key questions to understand its evolution as well as our solar system objects (planets, asteroids, comet, … ) as we know them today [4,5]. Since many decades, scientists try to unravel this composition by a wide variety of experiments, i.e. by laboratory analysis of Interplanetary Dust Particles (IDPs) available from the Cosmic Dust catalog obtained by NASA ER-2 aircraft [11], laboratory analysis of the Lunar soil samples brought back from the Apollo missions between 1969 and 1972, laboratory analysis of the Stardust particles collected at comet 81P/Wild [2,3], as well as laboratory analysis of meteorites. Besides the measurement on ground, first results from space based instrumentation are now available, i.e. the COSIMA instrument on-board Rosetta analyzed dust grains from comet 67P/Churyomov-Gerasimenko [1, 9]. Another indirect method of the analysis of elemental composition, is the analysis of the spectra obtained from the CILBO (Canary Island Long-Baseline Observatory) [10] funded by the SCI Faculty.
We will compare the chemical abundances obtained from several ground-based laboratories, space based experiments, and the CILBO spectral observations. The results obtained by the different sources are quite wide spread. Ground-based samples have the disadvantage that they might have been contaminated before their analysis. Space based experiments typically observe only one target, and it might be difficult obtain general conclusions. Meteor spectra analysis can provide the elemental abundances of many different dust particles from different cometary parent bodies (although we admit that our currently obtained observational (i.e. spectral) accuracy could be vastly improved).
To obtain quantitative results from the CILBO spectral calibration requires not only a thorough calibration of the data, but also the modeling of the meteor ablation in the atmosphere. The modeling is rather complex and we use the PARADE tool in collaboration with our colleagues from ESA/TEC-M as well as with the University of Stuttgart (Faculty funded). We report on the required modeling work and its current progress [6, 7], as well as the activities executed at the University of Stuttgart to proof the correctness of the modelling work with corresponding laboratory experiments.
The provided work would not be possible without Faculty funding!
[1] Bardyn et al., “Carbon-rich dust in comet 67P/Churyumov-Gerasimenko measured by COSIMA/Rosetta”, MNRAS 469, S712-S722 (2017)
[2] Flynn et al., “Elemental Compositions of Comet 81P/Wild 2 Samples Collected by Stardust”, Science, vol 314, (2006)
[3] Jacob et al, “Pyroxenes microstructure in comet 81P/Wild 2 terminal Stardust particles”, Meteoritics and Planetary Science 44, Nr, 10, 1475-1488 (2009)
[4] Lodders et al, “Presolar grains from meteorites: Remnants from the early times of the solar system”, Chemie der Erde, Geochemistry, vol 65, issue 2, pp 93-166 (2005)
[5] Lodders et al, “Solar System Abundances of the Elements”, in Lecture Notes of the Kodai School of ‘Synthesis of Elements in Stars’, ISBN 978-3-643-10351-3 (2010)
[6] Loehle, Rudawska, Koschny, Zender, et al., “Extension of the Plasma Radiation Database PARADE for the Analysis of the Meteor Spectra”, submitted
[7] Rudawska, Zender, Koschny, Smit, et al., “A spectroscopy pipeline for the Canary Island Long Baseline Observatory meteor detection system”, submitted
[8] Schramm et al, “Major element composition of stratospheric micrometeorites”, Meteorites, 24, 99-112 (1989)
[9] Stenzel et al., “Similarities in element content between comet 67P/Churyumov-Gerasimenko coma dust and selected meteorite samples”, MNRAS, 469 (2017)
[10] Koschny et al., “A Double-station Meteor Camera set-up in the Canary Islands”, Geoscientific Instrumentation, Methods and Data Systems, Vol. 2, No. 2, 2013, pp. 339–348. [11] Thomas et al., “Carbon in anhydrous interplanetary dust particles: correlations with silicate mineralogy and sources of anhydrous IDPS”, LPSC XXIII, (1992)
Summary
The talk will provide an overview of the elemental composition analysis using a diversity of methods, and then detail on the spectroscopy of meteors.
