"The study of the remanent magnetization (paleomagnetism) of extraterrestrial materials gives clues as to the history of the primitive solar system and its evolution. Indeed, paleomagnetic studies of meteorites provide a unique window into understanding early solar magnetic fields generated externally from planetesimal bodies (by the young sun during its putative T Tauri phase, or within the protoplanetary nebula), as well as magnetic fields generated within the planetesimals through convection of a molten core (dynamo field).After nearly two decades of relatively dormant activity, the field of extraterrestrial magnetism has recently reactivated, but many questions remain unanswered: Did the Sun pass through a T Tauri phase? How common were differentiated planetesimals with a convective core in the Early solar system? What was the timing of the differentiation of these planetesimals? Did the Moon, or Vesta have a core dynamo? What was the timing of these dynamos?The aim of this project is to participate to the current effort in answering those questions. More precisely we will focus on: 1) primordial fields in the solar nebula; 2) differentiation processes in asteroids; 3) Lunar magnetismWe will address these questions through detailed paleomagnetic studies of selected samples, using good practices that have up to now only seldom been applied to meteorites (like the determination of the nature of the natural remanence, with tests for shock and viscous remanence), advanced instrumentation (like small-scale magnetic mapping), and the interpretative framework provided by the recent progresses in the field of meteoritics (in particular thermochronology). Studied samples, that are already in our hands, will be carbonaceous (CV, CK, CM, CO, CI), enstatite and Rumuruti chondrites, aubrites, basaltic eucrites, and Apollo lunar rocks. They have all been carefully selected on the basis of their age and petrography, to provide answers to the above-mentioned questions."