The 2,397th Meeting of the Society

October 5, 2018 at 8:00 PM

Powell Auditorium at the Cosmos Club


Exploring Titan by Rotorcraft

Elizabeth (Zibi) Turtle

Planetary Scientist
Johns Hopkins University Applied Physics Laboratory

About the Lecture

Titan exhibits abundant complex organic compounds on the surface of a water-ice-dominated ocean world with Earth-like geologic and atmospheric exchange processes.  In addition to the level of organic synthesis that Titan supports, there have also been opportunities in Titan’s past for organics to have mixed with liquid water on Titan’s surface, for example at sites of cryovolcanic activity or impact melting.  Such interactions increase the potential for chemistry to have progressed beyond simple organic reactions, providing an unparalleled opportunity to study prebiotic chemistry, and to search for signatures of potential water-based and hydrocarbon-based life.  Thus, Titan is an ideal destination to seek answers to fundamental questions about the origins of life, such as: What makes a planet or moon habitable?  What chemical processes led to the development of life?

While the now completed Cassini mission discovered that the chemical reactions in Titan’s upper atmosphere generate much more complex organic molecules than had been expected, the compositions of the solid materials on Titan’s surface remain essentially unknown,  and the spacecraft revealed substantial compositional diversity across Titan’s surface.  Therefore it will be key for a future mission to be able to measure surface material compositions at a variety of locations:  mobility will be essential. 

This lecture will discuss the Dragonfly mission concept under study in NASA’s New Frontiers Program.  Dragonfly is a rotorcraft lander that would take advantage of Titan’s dense atmosphere and low gravity to use aerial mobility for wide-ranging in situexploration of Titan’s surface and atmosphere.  Dragonfly’s ability to fly will enable it to access different geologic settings 10s to 100s of kilometers apart, allowing Dragonfly to perform multidisciplinary science at multiple, diverse landing sites.  In its two year plus mission, Dragonfly’s revolutionary mobility will allow it to characterize prebiotic chemistry and habitability at dozens of diverse sites across Titan and to search for water- and hydrocarbon-based chemical biosignatures at each one.

About the Speaker

Elizabeth (Zibi) Turtle is a planetary scientist at the Johns Hopkins Applied Physics Laboratory.  She is the Principal Investigator of the Europa Imaging System (EIS) on Europa Clipper and Principal Investigator of the Dragonfly mission concept currently in competition under NASA’s New Frontiers Program.  Zibi also is an associate of the Cassini ISS and RADAR teams, a Co-Investigator of LROC on the Lunar Reconnaissance Orbiter.  Previously she was an associate of the Galileo SSI team.

Zibi’s research combines remote-sensing observations and numerical modeling, focusing in particular on impact cratering and tectonics on satellites and terrestrial planets, and on lakes and weather on Titan.

Zibi earned a BS in Physics at MIT and a PhD in Planetary Sciences at the University of Arizona.