Comets are believed to be remnants of the early solar system. The space mission Rosetta investigated the comet 67P/Churyumov-Gerasimenko from 2014 to 2016. On board the Rosetta orbiter was the MIRO instrument (Microwave Instrument for the Rosetta Orbiter). MIRO is a radiometer operating at millimetre and submillimetre wavelengths and measured the thermal radiation of the near subsurface of the comet. In order to interpret these measurements, several models are required.
In this project we derive the optical properties of the comet’s subsurface by matching the temperatures measured by MIRO with synthetic ones derived from these models.
Apart from the analysis of the MIRO data and the thermal modelling of the subsurface temperatures, the understanding of the radiative transport is essential. We developed a raytracing model, which does not only take emission and absorption into account, but also scattering.
The results were published in an article in the journal Monthly Notices of the Royal Astronomical Society:
Johanna Bürger, Thilo Glißmann, Anthony Lethuillier, Dorothea Bischoff, Bastian Gundlach, Harald Mutschke, Sonja Höfer, Sebastian Wolf, Jürgen Blum, Sub-mm/mm optical properties of real protoplanetary matter derived from Rosetta/MIRO observations of comet 67P, Monthly Notices of the Royal Astronomical Society, Volume 519, Issue 1, February 2023, Pages 641–665, https://doi.org/10.1093/mnras/stac3420
