Stress History of the Moon

Abstract

In the preceding chapter a survey has been given of the principal sources of heat inside an astronomical body whose mass is of the same order of magnitude as that of the Moon; and of the way in which this heat is likely to be distributed in the course of time. The time-dependence of the sources of radiogenic heat, together with the gradual cooling of lunar globe by escape of its thermal radiation into space, is bound to render the distribution of temperature inside the Moon a function of the time and, as such, will give rise to thermal stresses in its interior considered as an elastic solid, together with gravitational stresses produced by the self-attraction of the lunar mass. It is true that, in view of the relatively high temperatures likely to be prevalent in the lunar interior (as described in the preceding chapter), its mass need not necessarily behave as a perfectly elastic solid; and the possibility of departures from such a state will be discussed in the next chapter; the subject matter of the present chapter being reserved for a discussion of the behaviour of the lunar globe to gravitational, thermal, or other stresses to which the body of the Moon responds as an elastic solid.