The impact of the ESA Gaia mission in our knowledge of collisional families

Knowing the asteroid belt is the key to provide a reliable history ofour solar system. The main question which has been raised in the lastyears is: given our available data, does our classification ofasteroid into families provide a reliable history of the collisionalevolution of our solar system?We have done huge steps forward, but the real revolution isrepresented by the ESA Gaia mission. Starting from April 2018, Gaiawill provide observations of solar system objects with sub-mas accuracy,completely changing our vision of the asteroid belt.We present an overview of the main results achieved by the second Gaiadata release, focusing our attention especially on cratering families,which are the results of past collisions between asteroids that haveproduced many small fragments from a large parent body.We present our classification of cratering families, including theirage determination computed mixing dynamical and physical propertiesthat the asteroids share in the same family.