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Vinalia and Cerealia Faculae are bright and salt-rich localized areas in Occator crater on Ceres. The predominance of the near-infrared signature of sodium carbonate on these surfaces suggests their original material was a brine. Here we analyze Dawn Framing Camera's images and characterize the surfaces as composed of a central structure, either a possible depression (Vinalia) or a central dome (Cerealia), and a discontinuous mantling. We consider three materials enabling the ascent and formation of the faculae: ice ascent with sublimation and carbonate particle lofting, pure gas emission entraining carbonate particles, and brine extrusion. We find that a mechanism explaining the entire range of morphologies, topographies, as well as the common composition of the deposits is brine fountaining. This process consists of briny liquid extrusion, followed by flash freezing of carbonate and ice particles, particle fallback, and sublimation. Subsequent increase in briny liquid viscosity leads to doming. Dawn observations did not detect currently active water plumes, indicating the frequency of such extrusions is longer than years.

One of the main tasks of the Dawn mission is to characterize the potentially ice-rich crust of the dwarf planet Ceres. Ongoing studies reveal morphological features related to ice-rich material such as pits or particular landslides. Here we report the identification of ring-mold craters within the huge impact crater Occator. The Cerean ring-mold craters exhibit strong morphological similarities to the ring-mold craters on Mars, where ice-rich material is thought to be involved in such crater development. We discuss the occurrence of water ice reservoirs in the subsurface and assume that ice-rich material likely plays an important role in the development of ring-mold craters on Ceres. The occurrence of ring-mold craters on the surface of Ceres is not only a sign of water ice reservoirs in the subsurface but can also be used for the study of habitable zones on planetary bodies.

The dwarf planet Ceres has been explored by NASA's Dawn spacecraft with the goal of characterizing its geology, mineralogy, topography, shape, and internal structure. One outcome of this exploration is the production of geologic maps, meant to unveil the geologic history of Ceres. In this paper, we present the geologic map of the Ac-6 Haulani quadrangle (Lat. 22°S-22°N, Long. 0°–72°E) based on Low Altitude Mapping Orbit (LAMO) (∼35 m/pixel) data supplemented with color and spectral data, as well as a digital terrain model from the High Altitude Mapping Orbit (HAMO) (∼135 m/pixel, vertical accuracy of about 10 m). The 34 km diameter Haulani crater is one of the youngest features on Ceres and the most prominent one in the quadrangle. Haulani was formed on a topographical transition in north–south direction and shows a complex morphology with a variety of lobate flows and tectonic features. Multiple cracks and depressions around the crater indicate the failure of subsurface material. These were likely formed by the subsidence of material due to the instability of the subsurface. The mapping of Ac-6 Haulani suggests that Ceres is built up of layers with different material properties. We propose that Ceres has a solid crust and a variable ice-rich subsurface consistent with previous and recent models of Ceres' interior.

During the Dawn mission, observations at Ceres reveal numerous interesting post-impact modifications in and around craters. These modifications contain the deposition of extended plains material with pits, multiple lobate flows, and widely dispersed deposits that form a diffuse veneer on the preexisting surface.

Ceres´ surface is affected by numerous impact craters and some of them show features such as channels or multiple flow events forming a smooth, less cratered surface, indicating possible post-impact resurfacing. Flow features occur on several craters on Ceres such as Haulani, Ikapati, Occator, Jarimba and Kondos in combination with smooth crater floors, appearing as extended plains, ponded material, lobate flow fronts and in the case of Haulani lobate flows originating from the crest of the central ridge partly overwhelming the mass wasting deposits from the rim.