Robot sub, alien life, Jupiter’s moon

Research engineer Bill Stone of Stone Aerospace is developing a self-guided robotic submarine, called ENDURANCE, to look for alien life on Europa, an icy moon of Jupiter. In 2010, the ENDURANCE robot completed six months of tests here on Earth, at a frozen lake in Antarctica called West Lake Bonney.

Bill Stone: In my opinion, within our lifetimes, microbiological life will be shown to exist either on Mars or on Europa, or some other outer planet’s watery moon.

Bill Stone: The job that we were doing down there was to see if we could build a robot that could explore on its own, build three dimensional maps, navigate back home on those maps …And the idea with that is that if you see places where things are changing rapidly, that may suggest that there’s enough chemical energy there to support microbiological life.

The ice at West Lake Bonney was just a few meters thick, compared to the ice on Jupiter’s moon Europa which is believed to be at least a thousand times thicker. Astronomers think that there’s liquid water below that ice, and possibly life. But Stone said the West Lake Bonney was a good place to test the robot.

Bill Stone: The analog to Europa was very close, and even more so because the place we were going was completely unexplored. Below that ice cap, no human, no robot had ever been in this place.

The ENDURANCE successfully mapped and explored the water beneath the frozen lake.  Dr. Stone spoke more about the findings of the Environmentally Non-Disturbing Under-ice Robotic ANtarctiC Explorer, or ENDURANCE, mission.

Bill Stone We’ve spent six months down there now. It’s a NASA-funded project in their science directorate, developing concepts for their future robotic missions. In this particular case, we were testing concepts that would be applicable to a Europa lander mission, in which we put a lander on the surface of the ice. We melt through the ice. And then we go out and explore in the hypothesized sub-surface ocean, down there, looking for microbes.

EarthSky asked Dr. Stone about why Lake Bonney was chosen as the site to test ENDURANCE.

Bill Stone: This comes back to this idea of terrestrial analogs for what we’re going to try to do out there on Europa. Antarctica is frozen. It’s cold as hell. And it has these unexplored, subglacial lakes down there. Nobody’s been into them. The benefit of that is that we get to test the instrumentation, the robotics, the code that drives these machines. We’ve got over 100 thousand lines of code on the vehicle that tell it where to go, what to do.

Stone said the ENDURANCE also did a lot on its own.

Bill Stone: And ultimately, it will have to do everything on its own. Down there we were testing such things as, these things I mentioned: building maps, coming home on its own maps. Every day that we went out there, we would be typically running missions of four, four and a half kilometers. And then at the end of ten hours of exploration, mapping, chemistry, searching, things like that, it would have to find its way back to a tiny little soda-straw sized tube, and then come up through that to the surface, on its own.