2010 Annual Science Report
Arizona State University Reporting | SEP 2009 – AUG 2010
Astrophysical Controls on the Elements of Life, Task 3: Model the Injection of Supernova Material Into Star-Forming Molecular Clouds
The goal of this task is to determine how much supernova material can make its way into a forming solar system during its initial stages, when the gas that will form the star and the planets are collapsing from a molecular cloud. This supernova material may contain radioactive isotopes like 26Al, which is the primary mechanism by which asteroids melted and which may control delivery of water and other elements to terrestrial planets. This supernova material may also change the abundance ratios of bioessential elements.
We have made significant progress toward the goal of understanding how supernova ejecta may be injected into a nearby molecular cloud. Constraining the clumpiness of the ejecta was an important step that is now published by Ouellette et al. (2010) [see Task 4]. Initial calculations using FLASH were carried out by Beatrice Perret (adviser Frank Timmes), with assistance from Steve Desch; Perret left ASU before these were completed. Postdoc Liubin Pan, under the supervision of Evan Scannapieco and Desch, greatly advanced these numerical simulations. We are finding that injection into molecular clouds is quite efficient, provided ejecta are somewhat clumpy, and may naturally lead to observed abundances of radionuclides in meteorites. We are preparing a paper for publication, based on preliminary results that Pan presented results at AbSciCon 2010.
Additionally, in related work, Desch and collaborators have investigated the main competing theory for the origins of radionuclides, which says that there are few contributions to the solar nebula from supernovae. Our critique of this “X-wind” model and our rebuttal of these arguments were presented at the Lunar and Planetary Science Conference in March 2010, and were recently accepted for publication in the Astrophysical Journal.
PROJECT INVESTIGATORS:Steven Desch
PROJECT MEMBERS:Francis Timmes
RELATED OBJECTIVES:Objective 1.1
Formation and evolution of habitable planets.
Sources of prebiotic materials and catalysts