Studied area in the Ash region. a and b: geomorphological map of the studied area before and after perihelion (0.54 m pixel⁻¹). The different shape of the gravitational accumulation deposits (GAD) is due to different viewing angles between the two images (see Table 1). c and d: magnified image illustrating the different texture of the fine particle deposit (FPD) compared to the GAD, before and after perihelion. e: digital terrain model of the studied area, with a NAC image overlaid, and gravitational heights in color.