Abstract
The internal structure of the moon is examined in the light of the thermal state in which the present surface heat flow is used as a limiting condition. The thermal history is calculated for several models of the initially cold and hot moon. Main interests are: 1) to clarify the change of the thermal character of the moon when a gravitational separation of the iron core from the mantle is occurred; 2) to study the thermal history of the outer parts of the moon assuming a longenduring or an instantaneous formation of the crust resulting from the differentiation of the mantle.
The cold moon models give the observed heat flow provided that the average U concentration of the moon lies less than 1.5×10-8gr/gr. In this case, the core and the crust would not form.
In the hot moon, the core and crust are formed during the early stage and therefore the present surface heat flow is not excessive, even if the crust is present. The instantaneous formation of the crust together with the concentrations of U less than 1×10-8gr/gr are required to explain the present surface heat flow.
