Farside deep moonquakes and deep interior of the Moon

An effort to find farside deep moonquakes among the recently discovered nests of deep moonquakes has identified about 30 nests that are likely to be on the farside. Although only a few of them are locatable with currently available data and those few provide little new information about the deep interior of the Moon, the inferred distribution of the rest of these nests indicates that either the region of the Moon's deep interior within about 40 degrees from the antipode of the Moon is nearly aseismic or, alternatively, the very deep interior of the Moon severely attenuates or deflects seismic waves. Since this has important bearing on the origin and evolution of the Moon, future missions to the Moon need to be oriented toward resolving this uncertainty. Some limited data favor the attenuation/deflection hypotheses.