Thursday, March 8, 2007

Journey To The Center of The Sinkhole

Cave Carson © DC Comics
Scientists return this week to the world’s deepest known sinkhole, Cenote Zacatón in Mexico, to resume tests of a NASA-funded robot called DEPTHX, designed to survey and explore for life in one of Earth’s most extreme regions and potentially in outer space. Sinking more than 1,000 feet, Zacatón has only been partially mapped and its true depth remains unknown.

The system’s unusual hydrothermal nature is analogous to liquid oceans under the icy surface of Jupiter’s moon Europa. Technology developed to explore the sinkholes could be applied to future space probes of Europa, where scientists believe that deep cracks and holes in the ice offer a chance of finding extraterrestrial life.

Microbes which appear to be new to science have been discovered floating in deep water and lining rocks in Zacatón. Far below sunlight’s ability to penetrate, they may get their energy from nutrients welling up from hot springs. Gary and others speculate that previously undocumented life may await discovery in the murky depths.

Unique in the world of robotic explorers, DEPTHX is autonomous. The probe does not rely on instructions from humans to decide where to go or what to do. It creates 3D maps of previously unexplored areas as it swims along and then uses those same maps to navigate back to the surface.

Doctoral student Marcus Gary SCUBA dives with the DEPTHX probe during initial in-water tests at The University of Texas at Austin Applied Research Laboratories wet test facility.
Cenote Zacatón first achieved notoriety when two divers attempted to reach the bottom in 1994. One of them, Sheck Exley, died in the attempt. The other, Jim Bowden, survived, descending to a record depth of 925 feet. The outcome caused scientists to rethink ways that Zacatón could be explored safely. link

Journey To The Center Of The Earth (1959)