"In the last decades, both remote and in-situ observations have brought evidence to support the idea that small and medium-size (up to few hundreds of km) asteroids are made of loosely consolidated material, namely ""rubble piles"". The idea behind GRAINS is to study these peculiar celestial object by means of numerical simulations of gravitational aggregation and granular dynamics. The goal is to gain insights on the properties, dynamics and evolution of these objects. In particular, their internal structure is largely unknown, due to the lack of data caused by technological limitations in assessing them through remote observations and by the limited number of in-situ measurement opportunities.
Asteroids are of crucial importance for our society. They offer a unique and low-cost opportunity for deep-space technological development and represent the natural pathway for the human and robotic exploration of our Solar System. They have been identified worldwide by the major Space Angencies as the next step in the path towards the human exploration of Mars. In the last few years, asteroids have been identified as potential resources and asteroid mining has become a focus topic in the worldwide industrial community. Mining and harvesting resources from asteroids would be important not only for returing these materials to Earth, but also to provide low-cost and in-orbit fuel to support the exploration of our Solar System. Finally, asteroids represent a singular threat for humanity. In the past years, all major Space Angencies have started planetary defense offices, to monitor the trajectory of these objects and to help mitigating the risk of impacts.
The knowledge of asteroids and their interior is crucial to plan effective planetary defense mitigation actions, to exploit their resources and to fully leverage the opportunities they offer."