Lunar and Planetary Science XXXV (2004) 2146.pdf
HIGH RESOLOUTION DIGITAL ELEVATION MODELS OF PRISTINE EXPLOSION CRATERS.
T.G. Farr1, W. Krabill2, and J.B. Garvin3,1Jet Propulsion Laboratory, California Institute of Technology, Pasadena,
CA, 2Goddard Space Flight Center, 3NASA HQ.
| In order to effectively capture a realistic terrain | References:[1] http://aol.wff.nasa.gov/aoltm.html |
| applicable to studies of cratering processes and | [2] DOE (2000) DOE/NV-209-Rev 15. [3] Slate, JL |
| landing hazards on Mars, we have obtained high | et al. (1999) USGS OFR 99-554-A. [4] Bernard, |
| resolution digital elevation models of several pristine | D.E., M.P. Golombek (2001) Proc. AIAA Space |
| explosion craters at the Nevada Test Site. We used | 2001 Conf. , Albuquerque, NM. [5] Golombek, MP |
| the Airborne Terrain Mapper (ATM), operated by | and D. Rapp (1997) J. Geophys. Res., v. 102, p. |
| NASA’s Wallops Flight Facility [1] to obtain DEMs | 4117-4129. [6] Golombek, MP et al. (2003) J. |
| with 1 m spacing and 10 cm vertical errors of 4 main | Geophys. Res., v. 108, doi: 10.1029/2002JE002035. |
| craters and many other craters and collapse pits. The | Acknowledgements: Part of the research |
| main craters that were mapped are Sedan, Scooter, | described in this report was carried out at the Jet |
| Schooner, and Danny Boy [2]. | Propulsion Laboratory under contract with the |
| The 370 m diameter Sedan crater, located on | National Aeronautics and Space Administration. |
| Yucca Flat, is the largest and freshest explosion | |
| crater on Earth that was formed under conditions | |
| similar to hypervelocity impact cratering. As such, it | |
| is effectively pristine, having been formed in 1962 as | |
| a result of a controlled detonation of a 100 kiloton | |
| thermonuclear device, buried at the appropriate | |
| equivalent depth of burst required to make a “simple” | |
| crater [2]. Sedan was formed in alluvium of mixed | |
| lithology [3] and subsequently studied using a variety | |
| of field-based methods. Nearby secondary craters | |
| were also formed at the time and were also mapped | |
| by ATM. Adjacent to Sedan and also in alluvium is | |
| Scooter, about 90 m in diameter and formed by a | |
| high-explosive event. Schooner (240 m) and Danny | |
| Boy (80 m) craters were also important targets for | |
| ATM as they were excavated in hard basalt [3] and | |
| therefore have much rougher ejecta. This will allow | |
| study of ejecta patterns in hard rock as well as | |
| engineering tests of crater and rock avoidance and | |
| rover trafficability. | |
| In addition to the high resolution DEMs, crater | |
| geometric characteristics, RMS roughness maps, and | |
| other higher-order derived data products will be | |
| generated using these data. These will provide | |
| constraints for models of landing hazards on Mars [4, | |
| 5] and for rover trafficability [6]. Other planned | |
| studies will include ejecta size-frequency distribution | |
| at the resolution of the DEM and at finer resolution | |
| through air photography and field measurements, | |
| correlation of ejecta size and composition with radar | |
| and visible-thermal IR remote sensing signatures, and | |
| comparison of these results with similar | |
| measurements of Mars. | |
| The final DEMs, ancillary data sets, and derived | |
| data products will be made available to the | |
| community. |