To explore extraterrestrial oceans, NASA is testing underwater drones

Enceladus, Titan and Europa, these are the areas that NASA wishes to explore. These satellites of Saturn and Jupiter shelter, under their icy surfaces, immense oceans. To explore them, NASA is developing not new rockets, but… underwater drones.

“There are places in the solar system where we want to look for life, and we think life needs water. We therefore need robots capable of exploring these environments autonomously, hundreds of millions of kilometers from home,” explains Ethan Schaler, the principal researcher of the project, called Swim (Sensing with independent micro-swimmers).

Many parameters to measure

Driven by two propellers and equipped with four steering flaps, these self-propelled swimming robots should measure around twelve centimeters long. More massive prototypes measuring 42 cm long and 2.3 kg were 3D printed and tested last September in a swimming pool in California (United States).

The measurement of temperature, pressure, acidity, alkalinity, conductivity and chemical composition of an ocean would be carried out by means of sensors combined in the same chip, of a few square millimeters, developed by the Georgia Institute of Technology (United States). The submarines' battery would have up to two hours of autonomy, in order to be able to explore volumes of up to 86,000 cubic meters of water.

The objective, according to NASA, is to send a dozen robots simultaneously for each exploration, with a departure divided into four to five waves. They would arrive at their destination thanks to a cryobot, a robot whose objective is to cross a layer of ice. A new communication system allowing them to send information and track their position would also be on board.

Extreme temperatures… on Earth

For the moment, no date is planned for the launch of the Swim submarines. As part of their development, NASA is relying in particular on the experience acquired since 2022 through IceNode, an experimental fleet of autonomous robots which was to help measure the rate of melting of ice shelves, for example in Antarctica.

During tests carried out in March 2024 in the Arctic Ocean, in the Beaufort Sea, the external temperature of up to -45°C put a strain on the equipment (and the men), concedes the American space agency, which counts on the terrestrial variations of its research to convince of their interest.