Window into the Depths

Jefferson Grau inspected a viewport prior to installation on the human-occupied submersilble Alvin during a major upgrade completed in 2014. He was looking for bubbles or inclusions such as bits of dirt that could cause the viewport to crack under the extreme pressure of the deep sea. Grau was a technician at the time, but today is an Alvin pilot. His previous experience will serve him well—in addition to being able to maneuver the sub and collect samples for scientists, are expected to be able to troubleshoot problems and maintain and repair all systems on the vehicle. (Photo by Matthew Barton, Woods Hole Oceanographic Institution)