On a tiny moon of a distant planet, a billion kilometres from earth, a snake will soon slither through the uncertain terrain. The 13-ft long ‘snake’, weighing 100 kg, will scope its immediate surroundings, figure out how to pass through it, and either crawl through or curve itself sideways or extend itself across chasms without falling in — all the while looking for alien life on the icy moon of Saturn called Enceladus.

Named, tellingly, EELS (for exobiology extant life surveyor), the metal snake is a robot. Made by the US space agency NASA, the engineering marvel will function independent of human assistance. Unlike many other robots, it has no wheels to move on; instead, it moves on 3D-printed, horizontally placed screw threads. With this kind of build, the EELS can go to places where other robots never have.

“Imagine a car driving autonomously, but there are no stop signs, no traffic signals, not even any roads. The robot has to figure out what the road is and try to follow it,” says the project’s autonomy lead, Rohan Thakker. “Then it needs to go down a 100-ft drop and not fall.”

Enceladus is among those places that scientists believe have a better chance of hosting life. The Saturn moon is so far out that any control from the earth is out of the question. Hence the autonomous robot EELS.