New developments at the IAA cosmic dust laboratory

The interpretation of astronomical observations of comets and asteroids and of extrasolar objects such as protoplanetary and debris disks is crucial for understanding the origin and evolution of planetary systems. Collecting electromagnetic radiation scattered or emitted by dust particles present in these objects with powerful telescopes is often our only way to observe and characterized them. In situ observations are available for a handful of asteroids and short period comets, and many of these also rely on detecting light scattering by dust particles. Laboratory astrophysics and in particular cosmic dust light scattering studies are needed for the interpretation of these remote and in situ observations.

A large collection of ground- and space-based remote photo-polarimetric observations of comets now exist. These data suggest that the handful of short period comets observed in situ (1P/Halley, 9P/Tempel, 67P/Churyumov-Gerasimenko) may not be representative of all comets. Remote photo-polarimetric observations show that the dust envelopes of long period and interstellar comets have different characteristics than short period comets (e.g. size distribution and composition). These differences likely result from the different evolutionary paths of these objects. There are however very few – if any- laboratory studies on light scattering by realistic cometary dust analogues spanning the range of particle properties inferred from observations, including complex structures and compositions and the presence of ices. The aim of the Cosmic Dust Laboratory at IAA is filling the existing gaps in our understanding of the interaction between electromagnetic radiation and dust particles to enable a better interpretation of remote observations of comets, as well as of data gathered by future in situ missions such as Comet Interceptor.

In this talk I will present an overview of new developments at CODULAB since I joined the group in 2018. We are carrying out experimental and theoretical research, which includes synthesis of cometary dust analogues with Material Science techniques, new techniques for particle suspension, measurements of the scattering properties of these particles and light scattering numerical simulations. These studies are extended to climate science (atmospheric radiative transfer and aerosol retrieval) and exoplanetary systems (protoplanetary and debris disks and exoplanetary atmospheres). We are also exploring the application of light scattering laboratory methods to public health problems and medical diagnostic, such as the quantification of airborne pollen, detection of viral infections and diagnose blood cell illnesses.