Ponza, Italy, September 14, 2007—Fish swim past Italian scuba divers Debora Vissani, right, and Alessandro Brandetti as they sit on a platform anchored 50 feet (15 meters) underwater on the sea floor.

Vissani and Brandetti are two of six "aquanauts" who will spend 14 days submerged as part of an experiment to study the effects of living underwater for prolonged periods.

The divers have three diving bells for living space and a fourth bell for cooking, eating, and maintaining equipment. The aquanauts—members of the Explorer Team Pellicano—will be monitored by a medical staff and experts from Rome University and the city's hospitals, the news agency ANSA reported.

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