NASA’s Jet Propulsion Laboratory (JPL) is working on making a group of robots that could one day be used to look for signs of life under the icy shells of Jupiter’s moon Europa or Saturn’s moon Enceladus, according to a press release from the institution.
The way we explore new planets now is by sending landers and rovers that look for signs of life near where they land. Even though these methods work well, they severely limit the probe’s range and even the mission’s goals if the probe ends up far from where it was meant to land.
The NASA Ingenuity helicopter that went to Mars with the Perseverance Rover can scan the planet faster and farther and give the Rover information that helps it plan its missions. But in the future, NASA wants to send a lot of these kinds of friends to help us learn more about the worlds we want to explore.
“Sensing Using Individual Micro-Swimmers”
Ethan Schaler, a robotics mechanical engineer at NASA JPL, has a plan for such a mission: a swarm of swimming robots that can look for signs of life in the water under the icy shells of distant planets or even on their moons. These robots, called Sensing With Independent Micro-Swimmers (SWIM), would be about the size of a cell phone and have sensors to measure temperature, salinity, acidity, pressure, and salinity, as well as chemical sensors to look for biochemical signs of life.
Each of these robots would also have its own way to move and talk to each other using ultrasound, as well as its own computer. This might not sound too different from how ocean-exploring robots for planets would be made by space agencies. There is a small but important difference, though. Each of these robots is about the size of a cell phone, which means that a single ice probe could hold a lot of them.
A press release said that in their early stages, these wedge-shaped robots are only about five inches (12 cm) long and take up no more than five cubic inches (75 cm3) of space. Up to forty of these robots could fit in a cylindrical cryobot without taking up more than 15 percent of the payload. This would let more instruments be brought along.
On the faraway planet, how will the swarm of robots work?
Schaler thinks that a lander would launch the cryobot, which would then use a nuclear battery to melt its way through sheets of ice to a body of water below. The cryobot would then send out a group of robots that could explore the water body and send data back to the bot. These robots would be connected to the lander by a communications tether.
Since the heat from the cryobot could change the chemical makeup of the water, the swarm’s ability to probe a good distance away from the bot would tell us what the water is really like.
When needed, the swarm could also be told to work as a “flock,” collecting data as a group to either cut down on mistakes or measure the differences between sensors to find gradients, if there are any. “Life can start to happen if there are chemical gradients or energy gradients. We’d have to move upstream from the cryobot to be able to sense them “Schaler said in the statement to the press.
SWIM isn’t a part of any NASA mission right now, but they just got more money to make and test 3D-printed prototypes.