The PhD course in Astronomy Astrophysics and Space Science (AASS) -- jointly run by University of Rome "Tor Vergata", Sapienza University of Rome, National Institute of Astrophysics (Rome OAR, Rome IAPS, Teramo OAAb offices) and Italian Space Agency (ASI) -- trains internationally competitive researchers in the field of Astrophysics and Space Sciences, who carry out their research activity in the following reference areas: - Cosmology and Gravitation - Extragalactic Astrophysics - Planetary and Solar Physics - Space Science Techniques - Stellar and Galactic Astrophysics At the end of her/his course, the PhD student must acquire: - the ability to independently prepare a research program; - the technical-mathematical-IT and physical skills necessary to carry out a research program; - mastery of the English language necessary for a complete understanding of the scientific literature; - the ability to identify problematic aspects in planning and carrying out research; - the ability to work in a team also with coordination roles; - the mastery in presenting the results and knowledge acquired both in front of a specialist public and an audience of non-experts. The acquisition of these skills also passes through a didactic offer aimed at the specific topics of the doctorate and through the possible participation in national and international schools and workshops dedicated to doctoral students in Astrophysics and/or Space Sciences. The duration of the PhD course is three years. Each year one or more calls are issued in Italian and English for the public selection of candidates, where the number of scholarships envisaged, any positions without scholarship, and any proposed research topics are specified. The official language of the PhD program is English.