P41E-07
Craters on Pluto and Charon: The Influence of Low Gravities, Low Impact Speeds, and Unique Ices
Thursday, 17 December 2015: 09:18
2022-2024 (Moscone West)
Kelsi N Singer1, Paul Schenk2, William B McKinnon1, Stuart J Robbins3, Jeffrey M Moore4, Veronica J Bray5, John R Spencer3, S Alan Stern6, William M Grundy7, Ross A Beyer4, Carly Howett3, Cristina Dalle Ore8, Oliver L White9, Alex Harrison Parker3, Simon Porter3, Amanda Marie Zangari3, Leslie Ann Young3, Catherine Olkin3, Kimberly Ennico Smith4, Harold A Weaver Jr10 and The New Horizons Geology, Geophysics and Imaging Science Theme Team, and The New Horizons Surface Composition Science Theme Team , (1)Washington University in St Louis, St. Louis, MO, United States, (2)Lunar and Planetary Institute, Houston, TX, United States, (3)Southwest Research Institute Boulder, Boulder, CO, United States, (4)NASA Ames Research Center, Moffett Field, CA, United States, (5)University of Arizona, Tucson, AZ, United States, (6)Southwest Research Institute Boulder, Dept Space Studies, Boulder, CO, United States, (7)Lowell Observatory, Flagstaff, AZ, United States, (8)SETI Institute Mountain View, Mountain View, CA, United States, (9)NASA Ames Research Center, MS 245-3, Moffett Field, CA, United States, (10)Applied Physics Laboratory Johns Hopkins, Laurel, MD, United States
Abstract:
The surfaces of Pluto and Charon display a wide variety of crater landforms. Pluto and Charon present a unique regime to investigate cratering physics due to a combination of circumstances: 1) their relatively low gravities—Pluto’s gravity (~0.66 m s-2) falls between those of the large icy satellites of Jupiter and their mid-sized saturnian cousins, while Charon’s gravity (0.28 m s-2) is more similar to the latter, 2) the low primary impact velocities onto Pluto and Charon’s surfaces (average ~2 km s-1), and 3) the mix of surface ices likely present (e.g., N2, CO, CH4, H2O). We use available images from both the Long Range Reconnaissance Imager (LORRI; Cheng et al., 2008, SSR 140, 189-215) and data from the Ralph (Reuter et al., 2008, SSR 140, 129-154) color/composition instruments to characterize crater morphologies and ejecta characteristics. This presentation will focus on understanding formation of craters on Pluto and Charon (with reference to deformation/degradation processes described in other presentations) and will include comparison to icy satellites. We will also discuss what inferences can be drawn about impactor characteristics.
