On Titan, Dragonfly Will Peer at the "Chemistry That Led to Life" on Earth
Saturn’s moon Titan is a little less than half the size of Earth, with a hazy, dense atmosphere. It’s perfect for a Dragonfly.
This week, NASA announced that a rotorcraft-lander named Dragonfly would be sent on an eight-year journey to the planet, launching in 2026 and landing in 2034. Titan’s orbit is currently about 800 million miles away from Earth. And the probe going there is unlike anything we’ve ever sent to an off-Earth location: It will fly around the moon.
What Will Dragonfly Do When It Lands on Saturn’s Moon Titan?
Designed and built by Johns Hopkins Applied Physics Laboratory (APL), Dragonfly will sample surface materials and measure the compositions of Titan’s organic surface materials. It will explore a variety of locations to characterize the habitability of Titan’s environment, investigate the progression of prebiotic chemistry, and even search for chemical hints of water-based or hydrocarbon-based life.
"We can’t go back in time.
“We can’t go back in time on Earth to learn lessons about the chemistry that led to life,” Curt Niebur, NASA’s lead program scientist for New Frontiers, said in a televised announcement. “But we can go to Titan and look at that chemistry.”
Dragonfly, which will fly like a consumer drone, will use its propellers to fly to dozens of locations around the moon, as this animation below shows.
"Titan is just a perfect chemical laboratory.
“Titan is such an amazing, complex destination,” Elizabeth Turtle, Dragonfly principal investigator from APL, told reporters on Thursday. “We don’t know the steps that were taken on Earth to get from chemistry to biology, but we do know that a lot of that prebiotic chemistry is actually happening on Titan today. We are beyond excited for the chance to explore and see what awaits us on this exotic world.”
Turtle also said that Titan has had all the ingredients for alien life:
“Titan is just a perfect chemical laboratory to understand prebiotic chemistry — the chemistry that occurred before chemistry took the step to biology. We know that Titan has rich organic material, very complex organic material on the surface. There’s energy in the form of sunlight, and that’s what drives this really complicated chemistry in the atmosphere, and we know there’s been liquid water on the surface in the past. And so, these ingredients that we know are necessary for the development of life as we know it are sitting on the surface of Titan.”
Titan is larger than the planet Mercury and is the second-largest moon in our solar system. As it orbits Saturn, it is about 886 million miles away from the sun, about 10 times farther than Earth. Because it’s so far from the sun, its surface temperature is around minus-290 degrees Fahrenheit.
The team at Johns Hopkins APL will take full advantage of 13 years’ worth of data from NASA’s Cassini mission to choose its targets. Part of that mission was the Huygens probe, which was built and operated by the European Space Agency and became the first spacecraft ever to land on Titan in 2005.
Where on Titan Will Dragonfly Land?
Dragonfly will first land in the equatorial “Shangri-La” dune fields, which are similar to the linear dunes in Namibia in Southern Africa, before moving on to other areas in a series of “leapfrog” flights of around five miles, stopping along the way to take samples from compelling areas with diverse geography.
Dragonfly will fly to the Selk impact crater, where there is evidence of past liquid water, organics — the complex molecules that contain carbon, combined with hydrogen, oxygen, and nitrogen — and energy, which, together, make up the recipe for life.
Who Controls Dragonfly and How Does it Fly?
For all intents and purposes, the Dragonfly is an autonomous drone that will be controlled remotely from over 700 million miles away, back on Earth.
Dragonfly is about the size of a Mars rover, and four sets of twin rotors will provide full maneuverability. Since it takes over 80 minutes for radio waves to travel between Earth and Saturn, automatic navigation and hazard detection technology have had to be thoroughly tested and perfected.
If conditions are not conducive for a longer flight — it’s expected to be able to fly for up to eight or nine miles in one go — then the probe can make its way in a series of much shorter journeys.
Despite the fact that the atmosphere on Titan is methane, it’s still roughly the same density as that on Earth. This has enabled the Dragonfly to be effectively tested and its aerodynamics perfected.
It’s powered by a multi-mission radioisotope thermoelectric generator (MMRTG) nuclear power source that’s expected to provide a lifespan of about 2½ years once on the surface.
Tiny drills have been incorporated into the landing skid that will be used to take samples from Titan’s surface. There are cameras positioned all over the probe, including several high-resolution cameras and two that are placed on top of the high-gain antenna that’s used to receive instructions and transmit data.
“We’re not used to having to do this for space flight,” said Turtle, “but because Dragonfly flies, we actually have to think about aerodynamics. And so, we’ve got protection to make sure that we don’t have a lot of drag when we’re flying.”
“The antenna is designed to be able to move, to point toward earth, so we can communicate. And that means that we can use these cameras on the high-gain antenna to point around to take a panorama of the terrain surrounding the lander, at the different landing sites.”
Dragonfly will be part of a group of unmanned missions that have helped change our understanding of how the universe works, including the New Horizons mission to Pluto and the Kuiper Belt, Juno to Jupiter, and OSIRIS-REx to the asteroid Bennu. The mission is part of the NASA New Frontiers program that oversees exploration in our solar system.