Lunar and Planetary Science XLVIII (2017) 1329.pdf SPECTRAL CLUSTERING ON MERCURY HOLLOWS: THE DOMINICI CRATER CASE. A. Lucchetti1, M. Pajola2,3,1, G. Cremonese1, C. Carli4, G. A. Marzo5 and T. Roush3, 1INAF-Astronomical Observatory of Padova, Vicolo dell’Osservatorio 5, 35131 Padova, Italy (
[email protected] ), 2Universities Space Research Association, NASA NPP Program (Supported by an appointment at NASA Ames Research Center:
[email protected]), 3NASA Ames Research Center, Moffett Field, CA 94035, USA; 4INAF-IAPS Roma, Istituto di Astrofisica e Planetologia Spaziali di Roma, Via del Fosso del Cavaliere, 00133 Rome, Italy; 5ENEA Centro Ricerche Casaccia, 00123 Rome, Italy. Introduction: The Mercury Dual Imaging System [8], i.e. incidence angle of 30°, emission angle of 0° (MDIS, [1]) onboard NASA MESSENGER (MErcury and phase angle of 30°. On the photometrically cor- Surface, Space ENvironment, GEochemistry, and rected dataset we applied a statistical clustering over Ranging) spacecraft, provided the first global coverage the entire dataset based on a K-means partitioning al- of Mercury's surface with varying spatial resolution. gorithm [9]. It was developed and evaluated by [9-11] Early in the mission, high-resolution images showed and makes use of the Calinski and Harabasz criterion that specific areas exhibiting high reflectance and rela- [12] to find the intrinsically natural number of clusters, tive bluer in color were composed of shallow, irregular making the process unsupervised. A natural number of and rimless, flat-floored depressions with bright interi- ten clusters was identified within the crater and its ors and halos, often found on crater walls, rims, floors closest surroundings, see Fig.