"Until Marie Tharp's ground-breaking work in the 1950s, the floor of the ocean was a mystery--then, as now, we knew less about the ocean than we did about outer space. In a time when women in the scientific community were routinely dismissed, Marie's work changed our understanding of the earth's geologic evolution. While her partner, Bruce Heezen, went on expeditions to collect soundings (records of sonar pings measuring the ocean's depth across its...