A Study of Diversity Among Comets

University Of Texas At Austin, Austin TX

Investigators

Abstract

AST 0305823 Cochran Comets represent important tracers of the early history of our solar nebula because they are altered little from their time of formation. Knowledge of their composition can be used to constrain the chemistry of the region in which they formed. The chemistry, coupled with our current understanding of the dynamical evolution of the Kuiper belt and Oort clouds, can then be used as constraints for the temperature and pressure conditions in solar nebula models. In order to probe the degree of homogeneity of the nuclei, one needs a data set of a wide variety of objects which has been obtained and reduced in a uniform way. Dr. Anita Cochran and colleagues, at the University of Texas, will analyze a large database of extant comet observations in order to probe the degree of homogeneity of cometary nuclei. Over many years, they have used the telescopes of McDonald Observatory, coupled with a variety of spectrographs, to collect optical spectra of comets, including information on the distribution of the gas within the coma, resulting in a large database of observations which can be used to help determine the uniformity of the chemistry of comets. In this study, they will utilize their existing observations to study the diversity of cometary nuclei. The spectra will be analyzed to determine the production rates of various molecular species and to determine the relative composition of over 100 comets. These compositions will then be inter-compared to determine trends of composition with the formations of the bodies. The research will be published in peer-reviewed journals and submitted to the Planetary Data System Small Bodies Node Archive for future use by all scientists. This work is intended to be accomplished primarily by an undergraduate student at the University of Texas, under the supervision of Dr. Cochran. As such, not only is a scientifically important result expected, but the next generation of astronomers will be trained. At the end of the project, the student will be proficient in skills useful for future astronomical research, will have some experience at the undergraduate level with real research, and will be part of at least one publication in a refereed journal. The student will be supported to travel to a professional society meeting to present the results. In addition, the vast database will become available to the scientific community through publication and inclusion in the Planetary Data System Small Bodies Node archive. ***