On the importance of ices more volatile than H2O-ice for cometary activity
Final Report Abstract
Within this project we were able to build an experimental setup that is capable to measure the outgassing rates of volatile materials in the Knudsen regime. In a first step we have analyzed the outgassing properties of H2O, CO2 and SiO2 mixtures. The results of these experiments (outgassing rates of the ices and permeability of the formed dust layer) are used in thermophysical models to simulate the activity of comets. Well calibrated thermophysical models are of major importance to interpret the results of various space craft instruments (MIRO, VIRTIS, ROSINA, etc.). In the future, this experimental setup will provide the possibility to measure the outgassing rates of different ice species and to expand the already explored temperature regimes. Besides the measurements of the outgassing rates we have improved the sample production process. With our new particle dispenser, we are able to produce ~10x more ice particles per hour than before. Additionally, we have also carefully studied the size distribution of the produced H2O and CO2 particles.
Publications
- (2018). Monthly Notices of the Royal Astronomical Society, 479, 5272-5287
Gundlach, B., et al.
(See online at https://doi.org/10.1093/mnras/sty1839) - (2019). Monthly Notices of the Royal Astronomical Society, 483, 1202-1210
Bischoff, D., et al.
(See online at https://doi.org/10.1093/mnras/sty3182)
