The SS Andrea Doria capsized and sank on July 26, 1956, after colliding with another ship.

The crash killed 52 people and left the ocean liner lying on its starboard side off the coast of Nantucket.

Nearly six decades later, the ship took the life of a longtime Penn State professor.

Dr. Thomas Pritchard was a faculty member for more than 30 years as part of the neural and behavioral sciences department in the College of Medicine. According to a press release from the university, he “led an active research program in the study of taste for decades.”

He was lost at sea while diving the Andrea Doria’s wreck on July 21. Pritchard was an experienced diver, having picked up the hobby later in life. He was on an expedition to explore the wreck and headed down to secure a mooring line that connected his boat to the Andrea Doria.

After he and two crew members attached the line, they had a few minutes to explore the ship before they had to re-surface, a lengthy process because of the pressure so deep in the ocean.

They all ventured out separately, and the first crew member reached the surface about 75 minutes later, according to the Boston Globe. The next came up 15 minutes later, but Pritchard didn’t follow. A search and rescue team was called, but his body was never found.

Pritchard is the sixteenth scuba diver to die while exploring the wreck, which is considered by many to be the Mt. Everest of scuba diving. The water is filled with sediment that makes it almost black and reduces visibility. Fishing lines and nets attached to the boat are hazardous as well.

Pritchard is survived by his wife of 42 years, Christine; his children Michael, David, and Brian; and his grandchildren A.J., Brody, Brianna, Jude, Trey, and Chase.

“Tom was a treasured colleague and friend,” said Dr. Craig Hillemeir, dean of the Penn State College of Medicine. “Our deepest sympathies go out to his wife, Christine; his children and grandchildren, and his many friends.”

“He served on several key committees for the graduate program in Neuroscience, he co-directed the Neural and Behavioral Sciences course and laboratory for six years, and he co-wrote a related text: Medical Neuroscience,” Hillemeir added. “As such, he impacted the medical and graduate education of hundreds of students.”

The family asks that donations be made to the Central PA Leukemia & Lymphoma society in lieu of flowers. The charity is located at 2405 Park Drive, Suite 100, Harrisburg, Pa., 17110.