  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
Jerry Wasserburg and his collaborators to this exciting field of research. A
brief mention is also made to $\gamma$-ray line astrophysics. It provides an
interesting information on live short-lived radionuclides in the present
interstellar medium, and thus complements in a very important way the study of
extinct radionuclides in meteorites.
