NASA is planning to explore the subglacial oceans of gas giant satellites with a swarm of tiny robots

Subsurface oceans on gas giant moons are among the most promising locations to search for extraterrestrial life outside of Earth. NASA has given money to a research project that will develop a swarm of tiny swimming robots that will explore these alien seas for signs of aliens. Jupiter's moon Europa and Saturn's Enceladus are effectively huge icy balls with global seas buried beneath a thick frozen exterior shell. Scientists have long wondered if the conditions in those waters might be good candidates for alien life, with the Europa Clipper mission planned to undertake a series of close flybys in the 2030s to look for evidence of it.

However, a new concept may now use a fleet of smartphone-sized swimming robots to get up close and personal. As part of the NASA Innovative Advanced Concepts (NIAC) program, NASA has granted funding for the project known as Sensing With Independent Micro-Swimmers (SWIM). A long-term goal is to search for signs of life on other worlds. The proposed objective would be fascinating. First, a lander would touch down on the icy crust of one of these moons, followed by the deployment of a probe that uses heat from its nuclear battery to melt a tunnel through the ice to the ocean beneath it. Once there, the probe would release about 50 SWIM robots to begin exploring the frigid waters independently.

Each of these robots is wedge-shaped and measures about 12 cm (5 in) long, with its own propulsion system, onboard computer, ultrasound communications, and a suite of sensors for temperature, salinity, acidity, pressure, and chemicals. These robots could swim through the water like a school of fish collecting data to look for biomarkers of life. Intriguingly enough, by comparing readings from robots at the front and back of the pack, they could evaluate gradients such as temperature or salt concentration in real time.

The surface lander component would communicate with the SWIM swarm underwater, relaying data from the robots to Earth and new commands from the mission team to the bots. Other aquatic exploration robots have been proposed for exploring extraterrestrial seas, including a squid-like rover on Europa or a submarine to examine Saturn's moon Titan's liquid-methane lakes. However, according It would increase the amount of ocean that may be explored.

For now, it's just a concept that may or may not come to pass. However, there is a chance - the robot's inventor, Ethan Schaler of NASA JPL, was given US$600,000 in Phase II money from NIAC to continue development and produce prototypes over the next two years.