Electrical Heating of Meteorite Parent Bodies and Planets by Dynamo Induction from a Pre-main Sequence T Tauri "Solar Wind"

SEVERAL lines of evidence suggest that the time interval of early heating in the solar system was short in comparison with the total age of solid matter. The fast heating process has been attributed to radiogenic matter of short half life. Urey was the first to point out the possible significance of 26 Al in this respect 1 , but certain difficulties eventually led him to question this hypothesis 2 . Interest was again aroused with Reynolds's discovery 3,4 of radiogenic daughter 129 Xe and, together with 244 Pu fission tracks 5 , this attests to the presence of short-lived sources of radiogenic heat in the protosolar nebula. Fish, Goles and Anders have studied the hypothesis of extinct radionuclide heating in great detail and have provided specific estimates of the required nuclide concentration for melting and differentiation 6 .