Ceres, the dwarf planet located in the asteroid belt that separates Mars from Jupiter, Enceladus, Saturn’s sixth largest Moon, Jupiter’s Galilean moon Europa, and even it’s-a-planet/it’s-not-a-planet Pluto, they all have large amounts of liquid water under a frozen surface.
We’ve known this for a while now, but to date, our civilization is yet to send a mission to any of these places to take a really close look. Yet, knowing there’s a better chance of finding living things in any of these places (at least when compared with the odds of finding traces of long-gone life on dead Mars), several such efforts are now planned.
True, none of them will happen very soon, but now that the wheels are in motion a lot of other people have begun thinking of ways to make the exploration of these worlds easier.
You see, going to any of the worlds mentioned above is not like heading over to Mars and collecting samples. That’s because the layer of ice covering all that water is in places 40 km (25 miles) deep, so a lot of drilling, with tech not yet available, will have to be done.
One possible solution came to NASA Glenn Research Center’s Theresa Benyo, and it’s based on something called lattice confinement fusion. Quite the tongue twister, I know, and not exactly self-explanatory, so let us dive into it.
In essence, we're talking about a heated probe. Not just any probe, but one capable of surviving the immense pressures of the ice-water environment, and also the potential effects of being… eaten by alien life.
The probe would be nuclear-powered, but not in the traditional sense, meaning it will use neither plutonium-238 nor enriched uranium-235. Instead, it will be powered by said lattice confinement fusion reactor.
Like all forms of fusion, it produces energy by forcing two nuclei into a single, heavier one. In this case, a non-radioactive hydrogen isotope called deuterium (yes, the same stuff you see powering warp-capable starships in sci-fi movies) is used for fuel, squashed between the atoms of a metal solid (either depleted uranium or thorium), like a lattice.
Benyo says such a reactor would be smaller than conventional hardware, but still powerful enough to heat the probe just right for it to be able to pass through the thick ice. Once through, the machine should be capable of communicating its findings with the rest of us, but will also have to be properly equipped to return samples to the surface.
The idea might seem like something we won’t see happening for a very long time, yet NASA found it intriguing enough to award it an Innovative Advanced Concepts (NIAC) Phase I grant earlier this month.