"Comet 67P/Churyumov-Gerasimenko: coma structure formation through gas and dust emission"

In general, any cometary activity is difficult to predict and many comets are known for sudden changes in brightness, break-ups, or just disappear. Fortunately, the ESA Rosetta-mission target, comet 67P/Churyumov-Gerasiminko, is much more amendable to theoretical predictions. We have analyzed the gas [1,2] and dust environment [3] around comet 67P and applied methods also used in classical trajectory and wave-packet computation to map back the observed in-situ gas densities to the surface ice distributions. The dust embedded in the emitted gas stream serves as tracer of gas and dust flow and shows ray-type focal areas in the near-coma of the comet. We show that these structure are a faithful representation of the surface topography of the comet and the structure forms similar to a simple "kick-drift" model, sometimes used to model "branched flow". The sublimation of the ices on the nucleus induces changes in the orbital and rotational state of the comet, which we compare to the in-situ measured gas release [4,5]

References:
[1] Seasonal changes of the volatile density in the coma and on the surface of comet 67P/Churyumov-Gerasimenko, T. Kramer, M. Läuter, M. Rubin, K. Altwegg, Monthly Notices of the Royal Astronomical Society 469 S20 (2017), https://doi.org/10.1093/mnras/stx866

[2] Surface localization of gas sources on comet 67P/Churyumov-Gerasimenko based on DFMS/COPS data, M. Läuter, T. Kramer, M. Rubin, K. Altwegg, Monthly Notices of the Royal Astronomical Society 483 852 (2019), https://doi.org/10.1093/mnras/sty3103

[3] Dust and gas emission from cometary nuclei: the case of comet 67P/Churyumov–Gerasimenko, T. Kramer, M. Noack, D. Baum, H.-C. Hege, E. J. Heller, Advances in Physics: X, 3, 1404436 (2018), https://doi.org/10.1080/23746149.2017.1404436

[4] Outgassing induced acceleration of comet 67P/Churyumov-Gerasimenko, T. Kramer and M. Läuter, Astronomy and Astrophysics (2019), http://dx.doi.org/10.1051/0004-6361/201935229

[5] Comet 67P/Churyumov-Gerasimenko rotation changes derived from sublimation induced torques, T. Kramer, M. Läuter, S. Hviid, L. Jorda, H.U. Keller, E. Kührt, Astronomy and Astrophysics (2019), https://doi.org/10.1051/0004-6361/201834349

Transmisión vía Youtube en: bit.ly/YouTube_ICF

Participante: Dr. Tobias Kramer

Institución: Johannes Kepler Universität Linz, Austria

Fecha y hora: Este evento terminó el Miércoles, 10 de Noviembre de 2021