Physical Processes in the Rosette Nebula

The Rosette Nebula is an apparently spherical HII region which, though approximately 5000 light years distant, spans approximately 1.5 degrees of sky. Larger and much less luminous than the nearby Orion nebula, its faintness and angular size have made examination of the physical processes driving its shape, structure, and dynamics difficult. The spatial morphology of the nebula, which interacts with the associated Rosette Molecular Cloud complex, is obscured by the interstellar dust produced by previous generations of star formation. Our research seeks to construct a multispectral data set for the nebula and its environment, and through that to develop an observationally informed three dimensional model for the gas and dust densities, temperature, composition and motion. The distinctive ring of the Rosette is thought to be caused by radiation and winds from a central cluster of recently formed hot (OB) stars. The interaction of these stars with the nebula may be modeled based on physical first principles with CLOUDY and CLOUDY3D, thereby yielding a self-consistent understanding of the flow of energy from its stars and its appearance across the full spectrum from the ultraviolet to the radio. We are searching for evidence of prior episodes of star formation, and an understanding of the development of the heavy elements, molecules, and dust that are precursors to Earth-like planet formation. We have acquired narrow band images and long-slit spectra using wide-field instrumentation at Moore Observatory of the University of Louisville as the first phase of this project. Mosaics of the entire Rosette nebula with a 3.8 degree field of view and 4 arcsecond resolution have been produced in Hα, Hβ, [OIII], and [SII]. Additionally, an initial characterization of the dust density of the region achieved through analysis of the Hα/Hß line ratio from these images is presented.