T308 Geology of Dwarf Planets: First Results from NASA's Dawn Mission to Ceres (Posters)

Wednesday, 4 November 2015
9:00 AM - 6:30 PM
Exhibit Hall

INITIAL GEOLOGIC MAPPING OF THE AC-H-3 DANTU QUADRANGLE OF CERES USING DAWN SPACECRAFT DATA

Paper number: T308-3
Program: Technical Sessions
Time: 9:00 AM – 6:30 PM

Authors

Abstract

We here present an initial geologic map of the Ac-H-3 Dantu Quadrangle, one of fifteen mapping quadrangles of dwarf planet Ceres. The current geologic map is based on Dawn spacecraft data, in particular on Framing Camera (FC) image mosaics derived from Approach (~1.3 km/px) and Survey (~400 m/px) data as well as digital terrain models (DTMs) derived from stereo imagery. Mosaics from the High Altitude Mapping Orbit (HAMO, ~140 m/px) and Low Altitude Mapping Orbit (LAMO, ~35 m/px) phases will be incorporated as soon as the data become available (Fall 2015/ Spring 2016). The Dantu Quadrangle is located between 21-66˚N and 90-180˚E and includes the following dominant features: 1) the central and northern portion of the 124.6 km diameter impact crater Dantu; 2) crater chains and/or grooves oriented in an east-west direction; 3) a portion of the 84 km diameter impact crater Gaue, whose ejecta blanket covers the SW corner of the quadrangle. Dantu is a complex impact crater showing terraces, a central pit structure, concentric fractures, and smooth deposits on the crater floor. The materials interpreted to be ejecta deposits of Dantu show low crater frequencies and dominate the southern half of the quadrangle. These deposits appear to be relatively bright and correspond to parts of the #2 high albedo region observed by (1) with the HST indicating different composition and/or material properties than the surroundings. The east-west striking crater chains and grooves are mainly found in the southern half of the quadrangle. They seem to be connected to the crater chains found in Ac-H-4 Ezinu, the neighboring quadrangle to the east, and are potentially related to ballistic ejecta emplacement (see 2). Further work will be focused on Dantu crater and its complex interior and exterior as well as on relative and absolute crater-based surface ages of the mapped geological units.

We acknowledge the support of H. Hiesinger, S.H.G. Walter, R. Jaumann, T. Roatsch, F. Preusker, A. Nathues, T. Platz, M. Hoffmann, M. Schaefer, M.C. De Sanctis, C.A. Raymond, C.T. Russell, and the Dawn Instrument, Operations, and Science Teams. This work is partly supported by the German Space Agency (DLR), grant 50 OW 1101.

(1) Li, J-Y. et al. (2006), Icarus, 182, 143-160.

(2) Scully, J.E.C. et al. (2015), this conference.