

Search for Life on Titan

Saturn’s largest moon, Titan, is thought to have seas of methane with a landscape and atmosphere functioning much similar to our own. This is why NASA is developing a nuclear-powered rotorcraft-lander, deemed Dragonfly, to send to Titan’s surface. This car-sized drone will investigate the organic-rich terrain like never before, revealing whether or not this moon really is “primordial earth”, harboring the very beginnings of life. The reason we know anything at all about the composition of Titan is thanks to the European Space Agency's Huygens probe and NASA’s Cassini spacecraft. After disembarking from Cassini, the Huygens probe had a hazardous two and a half-hour descent to the moon’s surface – collecting data as it went.

NASA’s Nuclear Drone Will Search for Life on Titan

It was the first time scientists ever landed on a world in our outer solar system and the details from this mission provided a few insights. Titan has an atmosphere, winds, dry river beds and lakes, mysterious dunes, a possible subsurface ocean, cryovolcanoes, and, most excitingly, key ingredients for life, like methane, ethane propylene, nitrogen, and carbon. It was these qualities that propelled the creation of the Dragonfly mission. Dragonfly is led by a team out of John Hopkins University, but it was an international collaboration to get the unique duel quadcopter design and for good reason. So why is everyone excited about this mission? Well, traditional crafts, such as a lander or rover, are limited to their immediate location.

A rover couldn’t quickly travel vast expanses and a lander doesn’t move at all. But scientists found that Titan’s cold atmosphere, and predominantly nitrogen makeup provides a lower molecular viscosity than Earth's. This, paired with high densities means it’s much easier to get heavier items off the ground, like a car-sized drone. Plus, decades worth of advancements of autonomous multirotor technology made a rotorcraft a perfect deep space candidate. Scientists estimate Dragonfly will fly or “hop” from one location to the next faster than any Mars rover has driven in a decade.





Over two years, Dragonfly will have accumulated over a hundred and seventy kilometers of groundwork, and it’s prepared to do so, with a robust suite of instruments. Looking under the hood, the drone will be equipped with a Multi-Mission Radioisotope Thermoelectric Generator, better known as its nuclear power. This same system has been used before to power the Mars Curiosity rover. MMRTG’s work by converting heat from the natural decay of radioisotope materials, in this case, plutonium-238. It then uses solid-state thermocouples to convert the heat energy from that decay into electricity.

What makes this latest engineering design special is that it generates smaller increments of electricity, about 110 watts at launch, which will help prolong its lifetime in space. Plus, the MMRTG will power a battery that is roughly a quarter of the size of those found in Tesla electric vehicles. And Dragonfly’s innovations don’t stop there. The rest of the craft will be composed of highly-specialized instruments that will be used to explore the complex terrain on Titan. These will include, geophysical and meteorological sensors, cameras to look ahead at horizons and pointed below to look at dunes. And when it lands, Dragonfly will have an underbelly instrument that will fire neutrons at the surface and look for any gamma rays released to determine terrain types, like ammonia-rich ice or carbon-rich sand dunes.