Elisabetta Pierazzo

2006 Research Report

During 2006, Dr Pierazzo continued working on various research projects, while preparing papers and abstracts and new proposals relative to new research ideas.

Mars Research: Dr. Pierazzo and her team continued their investigation of Mars impacts focusing on characterization of mixed targets that is how to best model targets with mixed materials which is very important for realistic impact results. Our new investigation shows that the distribution of ice/water in the martian substrate (macroscopic vs. microscopic, slabs versus inclusions) affects the ice/water final temperature which could be significantly different the final post-shock temperature of the host rock (basalt in our simulations).

Impacts and lithospheres: Dr. Pierazzo and her team continue to investigate the effect of target lithologies on the impact cratering process. The nature of the target material is a very important parameter in impact cratering, influencing every stage of the impact event, and affecting the environment locally and/or globally. Our most recent work has involved more accurate investigation of the atmospheric penetration of a Canyon Diablo type impactor, combined with three-dimensional (3D) simulations of the initial stages of the Canyon Diablo impact event to investigate target and projectile disruption and melting. Another terrestrial crater under investigation is Popigai, responsible for the production of widely distributed microtektites/ microkrystites.

Impact Hydrocodes Benchmarking and Validation Project: Dr. Pierazzo is the leader of a collective effort from the impact modeling community to uniformly compare, validate and benchmark the computer models (hydrocodes) widely used by the impact community to model planetary scale impacts and their consequences, as well as by the defense community to model large explosions and the threat to civilization due to asteroid impact.

Origin and Evolution of planetary biospheres: Dr. Pierazzo is continuing her research on the environmental and climatic effects of large impacts on the Earth. She has teamed with scientists from the National Center for Atmospheric Research with the intent of using WACCM, the 3D atmospheric general circulation model with interactive stratospheric chemistry, to investigate the effect on atmospheric dynamics and chemistry of a Chicxulub type impact. Preliminary work consisted in importing the WACCM model to the PSI cluster, testing it and adding implementations to the code to model a pulse heating to the upper atmosphere to simulate the shock heating from the re-entering Chicxulub ejecta.

Education: Pierazzo has been leading an Education/Public Outreach effort, housed by PSI, entitled The Explorer's Guide to Impact Craters. In 2006 the team updated the website with the introduction of the virtual tours of the Barringer Meteor Crater and Ries craters, the preparation of the impact rock-kit manual, and the activation of the Ask-an-Expert link.

Papers

Pierazzo E., C.F. Chyba: Impact delivery of pre-biotic organic matter to Earth, Mars, and Europa. Comets and the Origin and Evolution of Life, Thomas P.J., Hicks R.D., Chyba C.F., McKay C.P. (Eds.), Series Advances in Astrobiology and Biogeophysics (Springer, New York). Invited. 137-168, 2006.

Pierazzo E.: Numerical modeling of impact cratering, 40th ESLAB Conf. Proc., European Space Agency Special Publication SP-612 (CD-ROM), 2006.

Fishbaugh K., E. Pierazzo, N. Barlow: Impact cratering in the solar system meeting summary, EOS 87(29), 283-284, 2006.

Abstracts

Larignon B.D., Pierazzo E., Goldstein D.B., Varghese P.L., Trafton L.M., Walker A.C., Moore C.H.: Direct numerical simulation of comet impacts and low-density atmospheric flow on the Moon, 38th Meeting of the AAS Division for Planetary Sciences (2006) Abst. #57.10.

Ivanov B.A., Pierazzo E.: Starting conditions for hydrothermal systems underneath Martian impact craters, 1st European Planetary Science Congress (2006) Abst. #A-00467.

Pierazzo E.: Numerical Modeling of Impact Cratering, 40th ESLAB Symposium: First International Conference on Impact Cratering in the Solar System (2006) Abst. #298069.

Canup R.M., Pierazzo E.: Retention of water during planet-scale collisions, 37th LPSC (2006) Abst. #2146.