Cosmic radioactivities

Abstract

Radionuclides with half-lives ranging from some years to billions of years presumably synthesized outside of the solar system are now recorded in ``live'' or ``fossil'' form in various types of materials, like meteorites or the galactic cosmic rays. They bring specific astrophysical messages the deciphering of which is briefly reviewed here, with special emphasis on the contribution of Dave Schramm and his collaborators to this exciting field of research. Short-lived radionuclides are also present in the Universe today, as directly testified by the gamma-ray lines emitted by the de-excitation of their daughter products. A short review of recent developments in this field is also presented.