Composition of solar system small bodies – SOLARYS

Observations of young-stellar objects have led to an astrophysical understanding of how planetary systems might form. As the disk evolves, sub-micron dust grains agglomerate into meter-sized dust balls, which will then coalesce to form the so-called planetesimals (1-1000 km). Most recently, it was shown that the radial structure of protoplanetary disk can be discontinuous. This is the reason why I introduce the notion of stratigraphy, i.e. discontinuous layers of possibly different composition.
Our Galaxy is hosting billions of stars and probably billions of planetary systems. But how original is the Solar System? My objective is to go back to the formation of the Solar System, retrieve its stratigraphy, in order to confront with observations within our Galaxy. For that, I want first to study planetesimals that preserve the primitive dust composition from different locations within the solar protoplanetary disk: primitive asteroids and comets. I will try to understand the optical properties of comets by exploring reflectance spectroscopy in the nano-phase world. I will for the first time investigate the spectro-photometry of primitive meteorites to answer whether or not they are related to primitive asteroids. And finally, while the origin of meteorite matrix is heavily debated, it still is the closest thing we have in hand to investigate early Solar System dust (together with IDPs). I will lead an innovative survey of matrix composition (bulk mineralogy, major and trace element composition), together with infrared spectroscopy in order to relate to astronomical observation. This will be done in reflectance and transmission, but also as at the nano-scale (Infrared and Raman), in order to characterize individual dust grains with vibrational spectroscopy. Last but not least, the D/H of water trapped in the matrix will be estimated, and could be related to the source region of each sample within the early Solar System.