Free Astronomy Magazine November-December 2018

15 NOVEMBER-DECEMBER 2018 SMALL BODIES teroids (which are probably fragments of larger bodies, with differentiated internal structure destroyed by collisional events), the carbonaceous ones are instead the sur- vivors of the planetesimal population from whose aggregation planets and moons of our solar system were born. For this reason, the study of the primordial material (non- differentiated and therefore not trans- formed by external or internal forces) that constitutes the carbonaceous asteroids like Ryugu is fundamental to understanding the origin and evolution of the inner plan- ets, in particular. That primeval material can also tell us where organic compounds and water on Earth might have come from. Moreover, more precise knowledge of the mineralogical composition and the physical and structural characteristics of Near-Earth Asteroids as a whole could be of vital im- portance if, in a distant day, one of them should point straight towards our planet. We will undoubtedly have the opportu- nity to update the important mission of Hayabusa2 during 2019 − stay tuned! hibits traits of hydrous minerals; regolith with weak or undetectable alterations due to water; primordial sub-surface rock. The expected amount for each sample is be- tween 0.1 and 10 grams. The choice of a carbonaceous asteroid like Ryugu is necessary if the goal is to collect and study pristine material from the solar system. Unlike the metallic and siliceous as- !