Studie der Eunomia Asteroidenfamilie mittels Spektroskopie

In this thesis ground-based optical and near-infrared spectroscopic and spectrophotometric observations of members of the Eunomia asteroid family are presented and their implications for the mineralogical structure of asteroids are described and discussed. The primary goal of the investigations was to determine to what extent the largest S-type asteroid of the solar system, (15) Eunomia, is in the mineralogical sense differentiated. The answer to this question contributes to the solution of fundamental main-belt evolutionary questions. For this purpose the most extensive spectral data set available to date of an asteroid family was obtained and analysed. A very exact detection of the colour variations of the surface of Eunomia and the discovery of colour variations of the surface of the asteroid lo was obtained. The spectral variations are attributed to mineralogical modifications of the surface composition. Furthermore, a large number of the small members of the family were observed in the wavelength range between 0.9 and 2.4 #mu#m. The results lead to an exact mineralogical classification of the asteroids. One important conclusion is that the genetic Eunomia family does exist. From the mineral compositions of the genetic members a model of the parent-body was developed. In addition some new correlations between the spectra and the orbital geometries were found. (orig.)Available from TIB Hannover: RA 437(2000-09) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman