A robotic vehicle designed for underwater exploration plunged repeatedly into the depths of Mexico's mysterious El Zacatуn sinkhole in late May, finding its previously undiscovered bottom 318 meters below the surface and generating a sonar map of its inner dimensions. The vehicle employed autonomous navigation and mapping systems developed by Carnegie Mellon University's Robotics Institute.

A NASA-funded expedition, including researchers from Carnegie Mellon University's Robotics Institute, will begin searching for the submerged bottom of Mexico's El Zacatуn sinkhole with a robotic submarine the week of May 14.