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Episode 123: Soaring over the surface of Titan: NASA’s Dragonfly Mission

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Dr Elizabeth Turtle and a scale model of Dragonfly. Credit: NASA

It is December 2034. A spacecraft launched from Earth in July 2028, enters Titan’s atmosphere at 5km/s. Around 2 hours later, it softly lands on the surface at less than 1m /s. Over the next three years, NASA’s Dragonfly mission, a rotorcraft the size of a small car, will chemically analyse the Titan’s atmosphere, ground and a little of its subsurface.

In this interview recorded on 24th April 2025 in Oxford during Breakthrough Discuss, Dr Elizabeth Turtle, Principal Investigator, on the Dragonfly mission to Saturn’s largest mission – Titan.

Some of the topics Dr Turtle covers include

  • Dragonfly’s scientific objectives to explore complex organic chemistry and understand the steps that occurred before biology took hold on Earth, helping us learn about our own chemical origins.
  • Dragonfly isn’t just landing; it’s designed to fly from place to place. Over its nominal mission lifetime of a little over three years, it expects to visit 30-40 different landing sites.
  • Flying on Titan is actually easier than flying on Earth because its atmosphere is four times denser and its gravity is only one-seventh of Earth’s.
  • An overview of the Dragonfly – large rotorcraft, technically an X8 octacopter, roughly the size of a small car or the large Mars rovers like Curiosity and Perseverance.
  • Dragonfly is powered by an MMRTG, a Multi-Mission Radioisotope Thermoelectric Generator, which provides both the electricity and the crucial heat needed to keep the lander’s interior warm in Titan’s frigid environment.

With a launch set for July 2028 and arrival at Titan in December 2034, Dragonfly promises to reveal the detailed chemistry of this unique world. Launch dates are always susceptible to change. The Cassini-Huygens mission that arrived at Saturn/Titan in 2004 was launched in 1997. Saturn orbits the sun every 30 years. If Dragonfly misses the July 2028 launch window, there may be another thirty-year wait!

Episode 122. Are we alone and the Breakthrough Initiatives

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Dr Pete Worden

For almost 70 years, astronomers have been listening to radio signals from beyond the Solar System, searching for “techno-signatures.” Data collected has increased many folds. Innovative technologies of digital signal processing and artificial intelligence analyse the data in ways never done before. Still, no clear, unambiguous techno or biosignatures have been detected.

You may have heard the announcement about an exoplanet (K2-18b) capable of supporting life, 124 light-years away. The data appears promising, but it is far from definitive.

A two-day Breakthrough Discuss conference held on 23rd and 24th April 2025 in Oxford England, took stock of the latest developments through three main sessions: “Forms of Non-Terrestrial Life”, “The Nature of Consciousness and Intelligence”, and “Detecting Life As We Do Not Know It”.

Breakthough Discuss was overseen by the Chairman of the Breakthrough Foundation, in this interview Dr Pete Worden. A former Brigadier. General, astrophysicist, professor and director of NASA Ames Research Centre talks about

– How and when he became involved with the Breakthrough Initiatives and current status of each
– His reflections on this year’s Breakthrough Discuss
– His interest in astronomy as a child
– What happened to his astronaut application to NASA
– His distant familial connection with his namesake – Al Worden Apollo 15 Command Module Pilot
– His assessment on where we are with the the search for extraterrestrial life and intelligence

Recordings of Breakthrough Discuss presentations are available on the YouTube channel

Episode 121 – Failed stars or successful planets?

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This episode was recorded at the Mount Teide Observatory with Jerry Zhang, a final year PhD student under the supervision of  Professor Eduardo L Martín and Dr Nicolas Lodieu at the Instituto de Astrofísica de Canarias. This class of object had been predicted for a long time but was first detected in 1995 from an observation conducted at the Mount Teide Observatory by a team of observers, including Jerry’s supervisor, Eduardo L Martín.

Jerry’s research focuses on Brown Dwarfs. Astronomical objects are somewhere in between stars and planets. Typically, their size is that of Jupiter, around 150,000km and a mass of between 15 and 70 times that of Jupiter. With such low mass (less than 0.08 of our sun), they can never reach the temperature or pressure in their cores necessary for nuclear fusion. They can never shine like our sun. They remain dim and small (brown and dwarf) throughout their lifetime.

Jerry’s most recent publication, arising from his Phd research, records the first detection of methane in an extreme metal-poor T dwarf.

Listen or download (click the three dots)

Pleiades cluster where Teide-1 was discovered in 1995. Credit: Author using Seestar S50
Pleiades cluster where Teide-1 was discovered in 1995.
Credit: Author using Seestar S50

Episode 120: Prof. Gengxin Xie. A Greenhouse on the Moon

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Chang’e 4. Credit Prof. Xei Gengxin

On Thursday, 3rd January 2019, some water was added to some seeds in a tiny greenhouse. The seeds, cotton, potato, Rape and Arabidopsis sprouted. 

Experiments like this have been conducted many times before. What was special about this one was that it was done on the surface of the Moon.

The guest on this episode is Professor Xie Gengxin from Chongqing University in central China. He was the  Chief Designer of this Bio experiment carried to the Moon on Chang’e 4 in January 2019. The interview was recorded in Milan during the International Astronautical Congress 2024.

In summary

  • The Chang’e 4 lunar mission by China landed on the far side of the moon and conducted a unique biological experiment involving cotton, potato, rape, and Arabidopsis seeds, along with fruit fly eggs and yeast, within a small, sealed greenhouse.
  • The primary goal of the experiment was to determine if plants could germinate and grow on the moon despite the lower gravity, lack of atmosphere, intense sunlight and radiation, and extreme temperature variations.
  • Cotton seeds successfully germinated 22 hours after water was added, marking the first instance of plant growth on the moon. These lunar seedlings grew faster than their counterparts in a control experiment on Earth and showed surprising resilience to the cold lunar night.
  • The experiment’s design included features like passive insulation, active temperature control, a small window for natural sunlight, and anti-fogging technology for the cameras monitoring the growth.
  • The findings suggest that lower gravity and higher radiation might have aided plant growth, and the experiment provided valuable insights and led to the development of technologies relevant to future space-based agriculture and the establishment of lunar habitats.
  • This biological experiment is considered a significant step in China’s lunar exploration program, which includes plans for a future lunar base (the International Lunar Research Station) and further research into creating sustainable ecosystems in space, potentially within lunar lava tubes.
Episode 120. A Greenhouse on the Moon.