Geomorphological and spectrophotometric analysis of Seth's circular niches on comet 67P/Churyumov–Gerasimenko using OSIRIS images
Year: 2017
Type: article
Abstract: We provide a detailed geomorphological and spectrophotometric analysis of the circular niches located on the Seth region of 67P using OSIRIS images. The features can be related to landslide events that occurred on 67P and shaped its surface, as the recent Aswan cliff collapse detected in the same region. We therefore provide an analysis of the area pre- and post-perihelion suggesting that no specific changes have been observed. To assess this, after performing a geomorphological map of the area that allows us to identify different terrain units, we computed the boulders cumulative size frequency distribution (SFD) of the niches, before and after the perihelion passage. The niches SFDs are characterized by a similar trend with two different power-law indices within the same deposit: lower power-law value (between −2.3 and −2.7) for boulders smaller than 5 m and steeper power-law value (between −4.7 and −5.0) for boulders larger than 5 m. These trends suggest that smaller boulders have evolved and progressively have been depleted (lower power-law index), while bigger boulders are more representative of the event that generated the deposit and are less degraded. Then, we perform the spectrophotometric analysis of this region comparing pre- and post-perihelion results. We found colour changes within the area, in particular brighter patches related to the presence of exposed water ice mixed to the refractory materials have been detected in the post-perihelion images.
Authors: A Lucchetti, M Pajola, S Fornasier, S Mottola, L Penasa, L Jorda, G Cremonese, C Feller, P H Hasselmann, M Massironi, S Ferrari, G Naletto, N Oklay, H Sierks, C Barbieri, P L Lamy, R Rodrigo, D Koschny, H Rickman, H U Keller, J Agarwal, M F A’Hearn, M A Barucci, J L Bertaux, I Bertini, S Boudreault, V Da Deppo, B Davidsson, S Debei, M De Cecco, J Deller, M Fulle, O Groussin, P J Gutierrez, C Güttler, M Hoffman, S F Hviid, W H Ip, J Knollenberg, J R Kramm, E Kührt, M Küppers, L M Lara, M Lazzarin, F La Forgia, L Z Lin, J J Lopez Moreno, F Marzari, F Preusker, F Scholten, X Shi, N Thomas, C Tubiana, J B Vincent
Institutions: Osservatorio Astronomico di Padova, Ames Research Center, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Observatoire de Paris, Sorbonne Paris Cité, Laboratoire d’études spatiales et d’instrumentation en astrophysique, Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR), University of Padua, Aix-Marseille Université, Laboratoire d’Astrophysique de Marseille, Max Planck Institute for Solar System Research, Consejo Superior de Investigaciones Científicas, Centro de Astrobiología, International Space Science Institute, European Space Research and Technology Centre, Centrum Badań Kosmicznych, Uppsala University, Technische Universität Braunschweig, University of Maryland, College Park, Université de Versailles Saint-Quentin-en-Yvelines, Institut Pierre-Simon Laplace, Laboratoire atmosphères, milieux, observations spatiales, Jet Propulsion Laboratory, University of Trento, Trieste Astronomical Observatory, Instituto de Astrofísica de Andalucía, National Central University, European Space Astronomy Centre, University of Bern
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2705937171