The global meter-level shape model of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lara, L. M.; Bertaux, J. -L.; Lamy, P.; Sierks, H.; Fulle, M.; Kührt, E.; Güttler, C.; Keller, H. U.; Mottola, S.; Pajola, M.; Barbieri, C.; Rodrigo, R.; Koschny, D.; Rickman, H.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.; Groussin, O.; Gutiérrez, P. J.; Hviid, S. F.; Ip, W. -H.; Knollenberg, J.; Kramm, J. R.; Küppers, M.; Lazzarin, M.; Marzari, F.; Naletto, G.; Oklay, N.; Thomas, N.; Tubiana, C.; Vincent, J. -B.; Preusker, F.; Scholten, F.; Lopez Moreno, J. J.; Matz, K. -D.; Massironi, M.; Roatsch, T.
Germany, United States, Sweden, Italy, France, Spain, Taiwan, China, Netherlands, Poland, Switzerland
Abstract
We performed a stereo-photogrammetric (SPG) analysis of more than 1500 Rosetta/OSIRIS NAC images of comet 67P/Churyumov-Gerasimenko (67P). The images with pixel scales in the range 0.2-3.0 m/pixel were acquired between August 2014 and February 2016. We finally derived a global high-resolution 3D description of 67P's surface, the SPG SHAP7 shape model. It consists of about 44 million facets (1-1.5 m horizontal sampling) and a typical vertical accuracy at the decimeter scale. Although some images were taken after perihelion, the SPG SHAP7 shape model can be considered a pre-periheliondescription and replaces the previous SPG SHAP4S shape model. From the new shape model, some measures for 67P with very low 3σ uncertainties can be retrieved: 18.56 km3 ± 0.02 km3 for the volume and 537.8 kg/m3 ± 0.7 kg/m3 for the mean density assuming a mass value of 9.982 × 1012 kg.