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    Rescuers spotted debris from the tourist submarine Titan on the ocean floor near the wreck of the Titanic on June 22, 2023, indicating that the vessel suffered a catastrophic failure and the five people aboard were killed. Below, Purdue University professor Nina Mahmoudian talks about vehicles for deep ocean research.

    Nina Mahmoudian: When we talk about water studies, we’re talking about vast areas. And covering vast areas requires tools that can work for extended periods of time, sometimes months. Having people aboard underwater vehicles, especially for such long periods, is expensive and dangerous.

    One of the tools researchers use is remotely operated vehicles, or ROVs. Basically, there is a cable between the vehicle and operator that allows the operator to command and move the vehicle, and the vehicle can transmit data in real time. ROVs can reach deep ocean — up to a depth of 6,000 meters. It’s also better able to provide the mobility necessary for observing the sea bed and gathering data.     Autonomous underwater vehicles provide another opportunity for underwater exploration. They are usually not tied to a ship. They are typically programmed ahead of time to do a specific mission. And while they are underwater they usually don’t have constant communication. At some interval, they surface, relay the data that they have gathered, change the battery or recharge and receive renewed instructions before again submerging.

    Crewed1 submersibles will be exciting for the public and those involved. However, they will be much more expensive compared with uncrewed explorations because of the required size of the platforms and the need for life-support systems. So, uncrewed vehicles provide better opportunities for exploration at less cost and risk in operating in inhospitable locations. Using remotely operated and autonomous underwater vehicles gives operators the opportunity to perform tasks that are unsafe for humans, like observing under ice and detecting underwater mines.

(https://theconversation.com, 23.06.2023. Adapted.)

1crewed: carrying or operated by a person or people on board.