Implantation of cosmic ions in Solar System ices.

Solid, atmosphere-less objects in the Solar System are continuously irradiated by energetic ions. Reactive ions (e.g., H, C, N, O, S) induce all of the effects of any other ion, but ill addition have a chance, by implantation in the target, to form new species containing: the projectile. An ongoing research program performed at our laboratory has the aim to investigate the implantation of reactive ions in many relevant ice mixtures. The results obtained so far indicate that some molecular species observed on icy planetary surfaces could not be native of that object but formed by implantation of reactive ions.