One of the most interesting worlds in this solar system is Titan, the largest moon of Saturn. It has a climate that in some ways mirrors that of Earth – but its climate features methane and ethane, rather than water. What do we know about Titan? What are its prospects for supporting life? We spoke with Conor Nixon, a scientist working at NASA’s Planetary Systems Laboratory. Dr. Nixon’s research interests include studying Titan’s atmosphere.
Why do you study the atmosphere of Titan?
Titan is really unique. It’s the only moon with a significant atmosphere, and that makes it in many ways more like the inner planets – Venus, Earth, and Mars – than like the other moons of the outer solar system. Of the three, Titan is most like Earth – its composition is mostly nitrogen and it has a weather cycle with wind, clouds, rain, and even rivers and lakes. However, it is also different from Earth in significant ways, since its rain and rivers and lakes are made of methane, not water, and it is also much colder.
Due to the lack of oxygen, complex chemical reactions take place in Titan’s atmosphere that are seen nowhere else, leading to the formation of large “organic” molecules that could be similar to the building blocks of DNA that were formed on Earth (or that arrived from space) eons ago. Truly a fascinating place to study whether you are a chemist, physicist, geologist, or biologist!
What are some exciting technological developments with regards to studying other worlds’ atmospheres?
For Titan in particular, the Dragonfly mission that has just been approved by NASA is really exciting. Dragonfly is a large quadcopter that will be the first ever built for spaceflight. It is about the size of a golf cart, or similar to the size of the Curiosity Mars rover. Dragonfly will lift off from Earth in 2026 and land on Titan around the year 2034, where it will begin a multi-year exploration of the surface and atmosphere, investigating for example Titan’s giant dune fields made of oily, resinous grains.
There are also exciting prospects for studying worlds beyond our solar system, specifically the atmospheres of exoplanets orbiting other stars. The launch of the James Webb Space Telescope in 2021 will make it the largest ever telescope put into space, and it will be able to tell us a lot more about the composition of exoplanet atmospheres – even whether they might be “habitable”, based on our assumptions about where life can exist.
What advice do you have for people interested in studying other planets?
There are many fun careers in planetary science. Most scientists take a lot of STEM classes at school and then go on to college to study a physical science major, such as physics, astronomy, chemistry, or geology. This can lead to careers ranging from using telescopes to study planets (astronomy), conducting field work to collect Martian rocks in Antarctica (geology), analyzing meteorite samples in a lab (geochemistry), and many others. Many people also work to design spacecraft and scientific instruments and have engineering backgrounds from almost every discipline. Amateur astronomers also contribute by monitoring planets and comets, and by alerting professional scientists to events such as storms, collisions, and comet apparitions.
You can also strengthen your resume by applying for internships at NASA, university departments, and elsewhere, volunteering at your local astronomy club or planetarium, and educating yourself beyond your regular school classes by reading popular science books, listening to podcasts or streaming science shows.