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Updated: Apr 6, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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COMETARY SCIENCE. The structure of the regolith on 67P/Churyumov-Gerasimenko from ROLIS descent imaging
S Mottola1, G Arnold2, H-G Grothues3
1German Aerospace Center (DLR), Institute of Planetary Research, Berlin, Germany. stefano.mottola@dlr.de.
Science (New York, N.Y.)
|August 1, 2015
Summary
Comet 67P
Area of Science:
- Cometary science
- Planetary geology
Background:
- The surface of comets is shaped by their activity.
- Understanding cometary surface structures provides insights into their evolution.
Purpose of the Study:
- To analyze the surface structure of comet 67P/Churyumov-Gerasimenko using high-resolution imagery.
- To investigate the processes responsible for shaping the comet's upper layer.
Main Methods:
- Acquisition of close-range images using the Rosetta Lander Imaging System (ROLIS) during Philae's descent.
- Analysis of surface morphology, particle size distribution, and regolith thickness.
- Modeling of erosion and mobilization processes.
Main Results:
- The Agilkia site on comet 67P exhibits a photometrically uniform surface covered by regolith (centimeter to meter-sized debris).
- High-resolution imaging reveals a granular surface without unresolved sand-sized particles.
- Regolith thickness varies from 0 to 2 meters; aeolian-like features suggest mobilization and erosion.
Conclusions:
- Cometary surface activity significantly influences upper layer structure.
- Abrasion from airfall-induced particle splashing is a likely mechanism for observed formations.
- The findings contribute to understanding cometary surface processes and evolution.
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