Apparent and real temporal variability of surface components of 67P/CG nucleus with Rosetta VIRTIS

International audience; The surface material of comet nucleus 67P/Churyumov-Gerasimenko contains components with a broad absorption band between 2900 and 3600 nm [1] that was revealed by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS, [2]) on the Rosetta spacecraft. Absorptions in this range of wavelengths are likely due to C-H and/or O-H chemical groups in various compounds [1, 3, 4]. In this study we investigate the distribution of this absorber across the surface of the comet nucleus, and apparent temporal variability on areas where the absorption band is the strongest.