Jason Barnes

Roving through the Air on Titan with Dragonfly

886 million miles from the sun sits a frozen moon larger than the planet Mercury, orbiting just beyond the ethereal rings of Saturn. Its gravity is only a seventh of that of Earth, yet its nitrogen-filled atmosphere is more than 50% denser. Freezing temperatures averaging -298°F allow for clouds of methane gas to rain down onto a solid crust, forming dark seas of liquid methane. Hydrocarbon sand dunes cover this strange world, broken up by large impact craters. And beneath its crust? A subterranean ocean of water, vaster than the combined oceans of Earth, and perhaps the host of alien life. This is Titan.

Dr. Jason Barnes addressed students at the January 23 seminar, titled "Roving through the Air on Saturn's Moon Titan." Dr. Barnes is the deputy principal investigator on the team of the NASA Dragonfly mission with a team that includes the department's Professor Jani Radebaugh. He received his Bachelor of Science in astronomy at the California Institute of Technology, a Ph.D. from the University of Arizona, and completed a postdoctoral fellowship at the NASA Ames Research Center. He is also currently a professor of physics at the University of Idaho.

The Dragonfly project is a $3.35 billion endeavor to explore the surface of Titan, one of Saturn's 274 moons and the second-largest moon in our solar system. Titan is of particular interest because it's one of the few places that scientists know of with a solid crust and thick atmosphere, making it strikingly similar to the Earth. The conditions are such that there is a potential for the existence of life both on the surface in organic-rich landscapes, and in the oceans underneath its surface. Although temperatures are extreme, the thick atmosphere and low gravity make for a relatively safe environment for landing craft to maneuver in. The Dragonfly team is particularly interested in the composition of Titan's organic material that makes up much of its surface, especially its sand dunes.

Dr. Barnes gave a detailed explanation about the design of the Dragonfly dual-quadcopter that they will be using to accomplish their mission. The lander is four meters long and weighs a staggering one metric ton, with a mass of about 1000 kilograms. It boasts four different stalks, two on each side, with two individual rotors of several feet in length on each stalk, allowing for rotation that gives the whole vehicle zero net angular momentum and making flying easier. It also features several different instruments. These include six cameras, a vacuum and a drill to take samples of the dirt, a mass spectrometer that measures the materials' molecular weight and composition, a gamma-ray/neutron spectrometer that measures the elemental composition, the individual atoms, of the material, and a seismometer that will be lowered down to the surface with a winch and used to identify the depth that Titan's crust extends and where its oceans begin. The lander is powered by a radioactive nuclear battery that's designed to last for years, feeding off of the passive decay of plutonium-238. The drone works completely autonomously, though it carries a flat-faced array dish that scientists will use to communicate and initiate commands. It can fly for up to half an hour, traveling at distances between five and ten kilometers. It's set to launch in July 2028 and will reach Titan in December 2034.

The drone will land near Selk Crater, an impact crater that scientists believe melted the ice and created a lake of water that lasted for approximately 1000 years. Dragonfly will look at and identify any effects that the water may have had on the organic material of the surface. This mission will give us a far greater insight into the conditions that form the precursor for life and what it may have looked like here on Earth billions of years ago. By exploring the far reaches of space, perhaps we'll gain a greater insight into ourselves.