Equipped with sonar, sensors, and cameras, ABE was a scout, cartographer, and bloodhound. It made high-resolution maps, “sniffed out” unusual chemicals emerging from the seafloor, and photographed biological communities and complex geological features. On a typical mission, it used all its capabilities.
First, ABE was programmed to “fly” about 250 meters above the seafloor using sensors measuring temperature, turbidity, and chemicals in the water to “sniff” plumes from hydrothermal vents. Then ABE was programmed to fly closer to the seafloor, making detailed maps of the seabed and, ideally, to intercept the stems of hot buoyant hydrothermal plumes of water rising up above the seafloor and home in on them. Finally, ABE was programmed to descend to right above the seabed and drive to and fro, very carefully—using techniques to avoid crashing into the rough rocky terrain—while taking photographs of seafloor features and deep-sea life.
(Illustration by E. Paul Oberlander, Woods Hole Oceanographic Institution)