August 20, 1998
Researchers from NASA's Jet Propulsion Laboratory are conducting these first-time engineering tests at the California aquarium as a precursor to an experiment that will place a scientific probe in an underwater Hawaiian volcanic vent later this year. The Lo'ihi Underwater Volcanic Vent Mission Probe will investigate an undersea volcano located 27 kilometers (20 miles) east of the Big Island of Hawaii at a depth of about 1,300 meters (4,250 feet).
"The purpose of using the Monterey Bay Aquarium kelp tank is to begin testing the instruments in an aquatic environment that contains some biological material that will stimulate and test the hardware," said JPL's Dr. Lonne Lane, principal investigator for the experiment. "The information to be gathered from these experiments at the aquarium and later in Hawaii will prepare us for future missions to difficult places like Antarctica's Lake Vostok (under 4 kilometers (2.5 miles) of ice), and below the surface of Jupiter's ice-encrusted moon Europa."
The use of the aquarium also provides a cost-effective, controlled environment for this first experiment. Open ocean opportunities with deep-diving submersibles are extremely limited and often expensive, Lane explained.
"As part of JPL's new astrobiology effort, we are bringing new instrumentation and approaches to areas that in the past have been deemed either very difficult or impossible to explore," he said.
"The long-range goal of this experiment is a multi-faceted investigation of deep ocean volcanic vents and sea floor cracks from which very hot water flow out into the deep ocean. The foremost question we are trying to answer is: Can and do simple biological species exist within the hot water vents? If so, what are the temperature limits for their survival and what are the chemical conditions they need for growth?" Lane said.
The search for life and organisms in extreme environments has prompted scientists to examine the thin, gelatinous (jellyfish-like) veils of material that have been previously observed at underwater volcanic hot water vents. Although there have been only a few observations of this material, on at least one occasion the white material has appeared to actually come from the vent throat. Measurements of thermal conditions inside the vents have produced a range of temperatures from near 80 C (176 F) to almost 350 C (662 F). The presence of life forms inside these vents would challenge what scientists believe is the accepted temperature range for life to exist. Currently the accepted temperature range is about -5 C to 110 C (23 F to 230 F), according to Lane.
After the August tests in Monterey, the team will take the probe to Hawaii in October.
"The goal of the Lo'ihi mission in Hawaii is to develop an instrumented underwater probe that can be placed inside these deep, hot water vents. The probe will determine temperature, chemical state, nutrient supply, the identity of organic material and conduct limited visual imaging," said JPL's Lloyd French, project lead and system architect for the probe mission. "The first experiments will concentrate on temperature and imaging the vent walls, while the chemical and spectroscopic instruments are being developed for the second year deployment. The scientific probe will be placed inside the underwater vent by a robotic arm controlled from within an underwater submersible."
The Lo'ihi mission is a joint venture between JPL and the University of Hawaii, with involvement from Hawaii Undersea Research Laboratories and the Monterey Bay Aquarium.
JPL, a division of the California Institute of Technology, is conducting the tests for NASA's Office of Space Sciences, Washington, DC.