Aluminum-26 as a planetoid heat source in the early solar system

The results of thermal model calculations which assume Al-26 as a heat source are presented. The relation between Al-26 content, the maximum central temperature obtained, and the time interval after formation until central cooling commences is elucidated. Because of the heating times required, these results constrain maximum permissible planetoid dimensions more severely than do previous calculations which assume a high initial temperature.