After Mars Helicopter Ingenuity, Dragonfly will be the next NASA drone helicopter to fly above the surface of another world when it arrives on Titan, the largest moon of Saturn, after launching from Earth in 2027.
Dragonfly will be much larger than tiny Ingenuity-- about the size of a small car-- although it is still undergoing design. It will conduct a mission lasting over two years to investigate samples on the surface of Titan’s organic oceanic world.
The dual quadcopter will be able to travel tens of miles in a single flight, powered by a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), like one used on the Perseverance rover on Mars, to provide 60 watts of power to charge onboard batteries. Ingenuity has relied on solar power, but the atmosphere of Titan is too dense to provide enough sunlight and Titan is much farther from the Sun than Mars.
Scientists hope to answer fundamental questions such as what makes a planet or moon habitable? Or what chemical processes led to the development of life?
NASA shared the insights of experts for Ingenuity and Dragonfly during an online YouTube event on Tuesday, taking questions from the public. Because Dragonfly will be size of a car, it will be hard to test it on Earth. “We will supplement drone flight tests with a lot of simulations to cover what we think we might experience on Titan,” said Nishant Mehta, deputy lead for the Dragonfly Mobile System at Johns Hopkins Applied Physics Lab.
The Dragonfly team has carefully watched the successful four flights of Ingenuity on Mars, recognizing that both craft are similar because they must be piloted autonomously. “With Ingenuity we learned they used a common cell phone processor, which was really inspiring and surprising to me,” Mehta said. (Ingenuity relies on a Qualcomm Snapdragon processor.)
Dragonfly—like Ingenuity—must also be able to survive extreme cold, which can reach nearly negative 300 degrees F. on Titan, compared to about 100 below on Mars.
“Survivability is one of the bigger challenges,” said Johnny Lam, an Ingenuity Mars Helicopter pilot at NASA’s Jet Propulsion Laboratory. “There’s a lot involved…a lot of work and testing,” including for a heater which has kept Ingenuity at an operating temperature to guarantee it will wake up every day.
Ingenuity has relied on Perseverance to transmit images and data to Mars orbiters which in turn relay it to Earth. But Titan, so far, has no orbiters and will rely on a high gain antenna to transmit images and data to Earth directly. It will have the ability to take one picture per second, but the challenge will be getting that data back to Earth, with data rates of 10 kilobits per second. “That’s not a lot, so we’ll be spending time optimizing what data to bring down,” Mehta said.
While Perseverance on Mars will be collecting Mars rocks and dust, the samples will not be analyzed until they are picked up on a later mission in 2026 or 2028 to return to Earth for analysis. Dragonfly, meanwhile, will be able to test the Titan surface and atmosphere and send back data by using a mass spectrometer and a neutron-activated gamma-ray spectrometer. It will also have meteorology sensors for monitoring the atmosphere. It will even conduct seismic studies to detect subsurface activity.
Scientists learned starting in 2004 with the Cassini orbiter and its radar and near-infrared imaging and a Huygens probe that was parachuted down to the Titan surface that moon has a salty ocean beneath the water-ice surface.
Cassini also revealed that Titan’s surface has rivers, lakes and seas of liquid ethane and methane. The methane can form clouds and even rain, which falls much slower than on Earth. That is because Titan’s atmosphere is four times denser than Earth’s and its gravity is about 1/7th of Earth’s. Both of those factors favor Dragonfly’s ability to fly even with its sizeable weight compared to Ingenuity’s four pounds.
Because Titan’s atmosphere is mostly made up of nitrogen with some methane, their molecules are split apart when exposed to sunlight and then recombine to form complex organic compounds. Those organic molecules are the reason scientists are so thrilled to travel to Titan and make measurements because organic molecules are the building blocks of life. Scientists last fall discovered a carbon-based molecule, C3H2, in Titan’s atmosphere using a radio telescope.
“Titan’s unique combination of abundant, complex, carbon-rich chemistry on its largely water-ice surface makes it an ideal location for such investigations,” APL says on its web site.
A short video from 2018 by JHU APL describes the purpose behind the mission:
Dragonfly’s mission to search for evidence of pre-biotic chemistry may sound like the stuff of science fiction, but the work is underway. NASA News Events Supervisor Jia-Rui Cook pointed out that Tuesday’s online event was staged for May 4th, widely known as the “May the Fourth be with you” from the Star Wars saga.