David Weber is probably best known for his Honor Harrington space opera series, but this is my favorite of his books. Colin MacIntyre is pilot of a NASA experimental moon vessel sometime in the not-too-distant future, with a simple-seeming mission: use a new "gravitonic" probe to map the mass distribution of the moon in detail. Unlike prior gravity surveys that merely use the slight variations in mass to give a very general idea of the mass distribution, the gravitonic probe should provide fine detail of structure and composition. But the [ Continue reading... ]