NASA Picks Mission to Fly Over the Dunes and Seas of Titan

NASA chose the Dragonfly mission as its next mission to the outer solar system today.  The cutting-edge spacecraft will fly over the surface of Saturn’s moon Titan to study its sand dunes and methane seas, stopping to analyze surface composition and looking for clues to how chemistry leads to biology and life.  While Titan is quite different from Earth, it also has some similarities and scientists hope to learn more about what happened on early Earth by studying Titan.

Dragonfly is the fourth in NASA’s New Frontiers series of mid-sized planetary exploration missions.  The first three are New Horizons, which visited Pluto in 2015, a Kuiper Belt object nicknamed Ultima Thule on New Year’s Day this year, and is continuing its journey into the far reaches of the solar system; Juno, which is orbiting Jupiter; and OSIRIS-REx, which is orbiting the asteroid Bennu getting ready to grab a sample and return it to Earth.

New Frontiers missions are chosen using an arduous competitive selection process that takes many years.  NASA narrowed the field from the original 12 proposals to two finalists in 2017:  Dragonfly and the CAESAR comet sample return mission. Those two teams, led by Elizabeth “Zibi” Turtle at the Johns Hopkins University Applied Physics Lab and Steve Squyres at Cornell University, respectively, have spent the last two years further developing their designs.  But NASA can only afford to build one.

Dragonfly was the winner today.

Dragonfly is a dual-quadcopter, basically a drone, that will be able to fly from place to place on Titan covering much greater distances than the rovers used on Mars.  In less than an hour, it will be able to travel tens of kilometers.  During its planned two-year mission, it will make many hops from its initial landing site, reaching a distance of several hundred kilometers.

Scientists already know a bit about Titan from the NASA/ESA Cassini-Huygens mission.  Cassini was a NASA spacecraft that orbited Saturn for 13 years before making a final plunge into its atmosphere in 2017.  Titan has held special interest for scientists for decades because of its thick methane atmosphere.  It was a special target for Cassini observations and for ESA’s Huygens probe that separated from Cassini and landed on Titan in 2005 providing the first ever glimpses of the surface.  It sent back data via Cassini during its 2 hour 27 minute descent and for another 72 minutes after landing until Cassini set below the horizon.  Imagery showed a surface with features that suggest rivers and lakes that scientists theorize could be filled periodically with liquid methane and ethane.

Now Dragonfly will allow a more thorough investigation of Titan, including sampling surface material to identify its chemical components, determining surface composition, monitoring the atmosphere, characterizing geological features, and performing seismic studies.

Dragonfly will launch in 2026 and arrive at Titan in 2034 after receiving three gravity assists from Earth and Venus.  NASA said that a launch vehicle will be selected about three years before launch.  Once it arrives, it will descend through Titan’s atmosphere, but unlike the Mars Curiosity rover and its “7 minutes of terror” from the top of the Martian atmosphere to landing on the surface, Dragonfly will have a comparatively leisurely descent of about two hours and the spacecraft will fly away from descent vehicle (the “backshell’) and look around before choosing its landing spot, as depicted in the video below.

Thomas Zurbuchen, the head of NASA’s Science Mission Directorate, marveled at what Dragonfly will do.  “It’s remarkable to think of this rotorcraft flying miles and miles across the organic sand dunes of Saturn’s largest moon, exploring the processes that shape this extraordinary environment. Dragonfly will visit a world filled with a wide variety of organic compounds, which are the building blocks of life and could teach us about the origin of life itself.”

Dragonfly will cost $850 million in FY2015 dollars not including launch and operations.

As with most NASA science missions, there are international partners in Dragonfly.  The Japan Aerospace Exploration Agency (JAXA) will provide a seismometer.  Germany’s DLR is offering to provide instrumentation to monitor heat shield performance.  Science co-investigators are from the United Kingdom, France, Japan and Germany.

Note: this article was updated with the cost and international partners.