Investigating Sub-Resolution Surface Properties of Comet 67P/Churyumov-Gerasimenko from Optical Photometry
Abstract
High resolution (<1m) multi-spectral images from Rosetta's Optical, Spectroscopic, and Infrared Imaging System (OSIRIS) narrow angle camera (NAC) of Comet 67P/Churyumov-Gerasimenko (67P) have revealed a wide variety of surface morphologies across the comet's surface at multiple viewing geometries. Key to understanding the processes that generate and modify these morphologies is to understand and quantitatively define the nature of their surfaces. Using the Rosetta data, we have produced phase curves for four characteristic morphologies (smooth plains, cauliflower plains, pitted plains and consolidated terrains) between 0° and 160° in 11 wavebands. We also separated the data temporally to search for pronounced, large-scale photometric changes between pre- and post-perihelion observations. We fit these phase curves to Hapke, (2012) photometric functions, and the best fit coefficients are compared to previously published fits of disk-integrated models. From this, we constrain roughness factors and dielectric constants of each region that are indicative of variable levels of erosional and active processes in each terrain. These findings will be discussed in the context of their importance to the general surface properties and evolution of 67P.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P23A3466M
- Keywords:
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- 5215 Origin of life;
- PLANETARY SCIENCES: ASTROBIOLOGY;
- 6024 Interiors;
- PLANETARY SCIENCES: COMETS AND SMALL BODIES;
- 6218 Jovian satellites;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6280 Saturnian satellites;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS