ENDURANCE: Missions to Antarctica and
Paths to Advanced Sub-Glacial Science Autonomy
Dr. William Stone
Stone Aerospace, Austin, Texas
Permanently ice-covered liquid water environments are among the leading candidate sites for finding evidence of extant life elsewhere in our solar system (e.g. on Europa and other Galilean satellites). In order to have the proper tools and strategies for exploring the ice-covered planetary environments, we have developed an autonomous underwater vehicle (AUV) which has generated, for the first time, 3-D biogeochemical datasets in the extreme environment of perennially ice-covered Antarctic dry valley lakes. ENDURANCE (Environmentally Non-Disturbing Under-ice Robotic ANtarctic Explorer) is a highly maneuverable, hovering autonomous underwater science platform developed under NASA funding. ENDURANCE had the specific mission of descending through a 5 meter deep melt hole in the ice cap of West Lake Bonney inTaylor Valley, Antarctica and conducting three autonomous science tasks: 1) measuring the 3D water chemistry of the lake; 2) mapping the underwater face and grounding line of Taylor glacier where it enters the lake; 3) charting the bathymetry of the lake bottom; and then 4) returning safely on its own to the melt hole from more than 2 kilometers radial range. The dataset for West Lake Bonney (WLB) includes unprecedented high resolution sonar maps of the entire lake, 3-D maps of temperature, conductivity, pH, REDOX, photosynthetically-active radiation, chl-a fluorometry, and dissolved organic matter. Variation in ice thickness across the lake was acquired both by sonar and pressure transducer readings while the vehicle was at rest under the ice. Many features of ENDURANCE represented radical changes and improvements over its highly successful predecessor craft, DEPTHX.