NASA's Dragonfly to search Titan for life – Earth-like or otherwise
Saturn’s moon Titan is one of the most intriguing places in the solar system, so much so that NASA is planning to send a rotorcraft there in the mid 2030s. Now the science team behind this Dragonfly mission has outlined its science goals and objectives, with the search for signs of life high on the list.
Titan is surprisingly Earth-like – it has a thick atmosphere and it’s the only other place we know of that has liquid lakes, oceans, rains and rivers. The key difference is that these aren’t filled with water, but liquid methane and ethane. As such, Titan could turn out to be home to strange alien forms of life that use different biological processes to Earthlings.
In 2019, NASA selected the Dragonfly mission to explore this weird world. As the name suggests, the mission would include a robotic helicopter of sorts that would hop around the surface, like a bigger version of the Ingenuity drone that’s currently exploring Mars alongside the Perseverance rover.
And now, the science team behind the Dragonfly mission has outlined its goals and objectives. The underlying theme is life – specifically, whether Titan does, has or could host life in some form. Scientists have already detected some possible markers of prebiotic chemistry, such as organic compounds and molecules that resemble those thought to have existed on early Earth. So the craft will investigate whether the conditions are right for life to take hold, by studying the global methane cycle, how the atmosphere interacts with surface material, and where water might mix with organics.
Another key is to figure out if this would be “life as we know it” or not – that is, whether it’s water-based like us, or if it uses liquid hydrocarbons that are available in Titan’s lakes and seas. Importantly, Dragonfly will search for chemical biosignatures that could indicate past or present life of either kind.
The team has selected a landing site that would give them access to places that could hold the answers to all of those questions. Dragonfly will initially set down among the dunes near the equator, where it can sample organic sediments, then explore the interdune regions to sample water ice. The craft would stay in each location for one full Titan day (about 16 Earth days) before taking to the skies and moving to a new spot. Ultimately, the craft would head for Selk Crater, an 50 mile wide crater that may yield signs of water having mixed with surface organics.
“Titan represents an explorer’s utopia,” says Alex Hayes, co-author of the study. “The science questions we have for Titan are very broad because we don’t know much about what is actually going on at the surface yet. For every question we answered during the Cassini mission’s exploration of Titan from Saturn orbit, we gained 10 new ones.”
We still have a while to wait before we might get answers though. Dragonfly is set to launch in 2026 and won’t arrive at Titan until 2034. But when it does, the images and data we get back may be some of the most fascinating we’ve ever seen.
The research was published in the Planetary Science Journal.
Source: Cornell University