A robotic probe developed for NASA’s Astrobiology Science and Technology for Exploring Planets (ASTEP) Program is scheduled to perform a series of test dives in an ice-covered lake in Wisconsin during the week of February 11, 2008. These tests are intended to demonstrate the probe’s ability to function in a cold-water environment before its builders take it to Antarctica for a full-blown demonstration.

This autonomous underwater vehicle (AUV), called ENDURANCE – the Environmentally Non-Disturbing Under-ice Robotic ANtarctic Explorer – is a $2.3 million project intended to demonstrate concepts for exploring the ice-covered ocean on Jupiter’s moon Europa. While underwater exploration on Europa is far in the future, it is not too soon to start developing the technology that will be needed for such a mission. The ENDURANCE project is expected to contribute to defining mission concepts for exploring Europa.

ENDURANCE is designed to swim untethered under ice, creating three-dimensional maps of the underwater environments it explores. It will collect data on conditions in those environments and take samples of microbial life. It is a follow-on to the Deep Phreatic Thermal Explorer (DEPTHX), a successful ASTEP project that completed a series of underwater field tests in Mexico in 2007.

ENDURANCE is a rebuilt DEPTHX, outfitted with a new instrument package designed for exploring and sampling Antarctica’s Lake Bonney, a 2.5 mile long, 1 mile wide, 130 foot deep perpetually ice-covered body of water located in the continent’s McMurdo Dry Valleys.

The February field testing, taking place in Lake Mendota on the campus of the University of Wisconsin at Madison, is intended to prove that ENDURANCE is suited to operating in a cold environment.

ENDURANCE was transported by truck from Texas, where it was assembled, to Wisconsin. The schedule for ENDURANCE testing in Wisconsin tentatively includes:

  • February 11: vehicle checkout and “dunk test” in the Water Science and Engineering Laboratory of the Center for Limnology, a heated facility on campus. (The dunk test involves suspending ENDURANCE from a crane and submerging it in water for about the length of the planned mission in Lake Mendota to observe how the robot’s systems perform as it cools down.
  • February 12: deployment of ENDURANCE beneath the ice-covered surface of Lake Mendota to perform general maneuvering and navigation tests.
  • February 13: sub-ice power cycling tests and surface radio location tests (assuming the ice is safe to walk on).
  • February 14: multibeam sonar and machine-vision tests (if systems are operational).
  • February 15: full mission simulation.

Plans call for ENDURANCE to be shipped to Antarctica later this year for operations during the 2008-2009 field season. There, if all goes well, ENDURANCE will map Lake Bonney for a month, then do a second mapping in 2009. Data gathered will be relayed back to UIC’s Electronic Visualization Laboratory to generate various three-dimensional images, maps and data renderings of the lake, according to ENDURANCE Principal Investigator Peter Doran of the University of Illinois, Chicago (UIC).

If ENDURANCE works well in Lake Bonney, the next goal is to send a much smaller version of ENDURANCE to probe Antarctica’s massive, Lake Ontario-sized Lake Vostok, which sits under more than two-and-a-half miles of ice. Lessons learned from mapping Lake Bonney will be useful in developing strategies for exploring Vostok and icy planetary bodies, like Europa.

Co-investigators on the ENDURANCE project include Andrew Johnson, associate professor of computer science at UIC; John Priscu, professor of land management and environmental sciences at Montana State University; and planetary scientist Christopher McKay of the NASA Ames Research Center in Mountain View, California.