colloquium Giovanni Poggiali: Looking from micro- to macro-scale: how the exploration of the Solar System can benefit from laboratory experiments on analog and returned samples

The exploration of the Solar System’s rocky surfaces of planets and minor bodies using remote sensing benefits from multiple sources of data: from ground-based observations, to orbiter and lander flybys, to returned samples of extraterrestrial material. However, the more data we acquire, the more it becomes clear that our current interpretation techniques (both laboratory and modelling), although improving, are still not sufficient to fully understand our observations. Indeed, the interpretation of remote sensing data could not be separated from intensive laboratory work, which provides a powerful tool for revealing the surface physical state and composition of rocky surfaces. The analysis of complex mixtures of analogous materials remains one of the key laboratory investigations to support remote sensing interpretation, but it is also one of the most challenging experiments, especially when multiple components are used. This talk gives a general overview of the main results from the literature on the efforts to use laboratory data to interpret infrared observations. Some new measurements on the mixing effect of different grain sizes and dark materials are also presented.