Why is NASA sending 'Dragonfly' to Titan? Here are five reasons
NASA is planning to send a drone-like spacecraft Dragonfly to Titan, Saturn’s largest moon to dig further into a world that has become one of the most important targets of exploration. Dragonfly, as the mission is called, will be capable of soaring across the skies of Titan and landing intermittently to take scientific measurements, studying the world’s mysterious atmosphere and topography while searching for hints of life on the only world other than Earth in our solar system with standing liquid on its surface.
Dutch astronomer Christiaan Huygens discovered Titan in 1655, calling it simply “Luna Saturni,” or Saturn’s moon. It was later renamed after a group of mythological Greek deities called Titans.
Here are five reasons Titan is so enticing:
1. It’s the only moon in our solar system with a thick atmosphere
Like the Earth, moon have atmospheres too, but they are so tiny that they are barely there. Among the solar system's many moon, Titan's atmosphere is the thickest.
Titan’s dense atmosphere offers a key benefit to scientific exploration, especially combined with its low gravity (1/7th of Earth’s) and frigid temperatures (-290 Fahrenheit, -179 Celsius, 94 Kelvin). These three features will help Dragonfly stay easily aloft above Titan’s surface and to fly faster and farther with little energy. In fact, Dragonfly is expected to fly more than 100 miles (160 kilometers) over a nearly three-year mission — that’s almost double the distance traveled by all the Mars rovers combined.
2. Its atmosphere is more similar to Earth’s than any other
Titan’s atmosphere is made mostly of nitrogen (about 95%), like Earth’s (78%). It also contains about 5% methane, plus a hint of other carbon-rich compounds.
A only difference between the two worlds is oxygen, which is absent on Titan, but makes up 21% of Earth’s air.
3. There’s intriguing chemistry happening there
It takes only two ingredients in the atmosphere — methane and nitrogen — to unleash a complex web of organic chemistry that makes Titan unique and interesting to scientists. After radiation from the Sun splits each of these molecules apart, their component atoms of carbon, hydrogen and nitrogen can recombine to form a variety of complex organic compounds that settle on the surface. Called “organic” because they contain carbon, these types of molecules are the building blocks of life on Earth. Thus, scientists are eager to see which compounds are on Titan and whether they are similar to the ones that could have seeded life on Earth.
4. It’s a real-time science experiment that can’t be reproduced in a lab
Scientists are still working to understand how life started on Earth when the planet was about a billion years old.
Many scientists believe that the moon could be a virtual laboratory for prebiotic chemistry that’s been ongoing for ages. When Dragonfly arrives on Titan in 2034, it will pick up the results of these experiments at several locations on the moon’s surface with a variety of geologic histories.
5. It has spectacular similarities with the Earth, but with some curious twists
Titan’s terrain, and even its landscape, looks eerily similar to Earth’s.
Dragonfly’s landing site in the equatorial region called Shangri-La, for instance, features dunes that could easily be confused with those of Namibia, a country in southern Africa.
There are other spectacular similarities: Like Earth, Titan is carved by flowing rivers and lakes, and seas named after mythical sea creatures. But these bodies of liquid, some as big as North America’s Great Lakes, are made of methane instead of water. As the gas flows across the surface, wearing away rocks along its path, it produces hills and valleys that are reminiscent of those in White Canyon, Utah and Guangxi, China.
The rocks strewn about Titan’s surface look familiar, too. Yet they’re made of water ice that stays frozen solid in the moon’s unfathomably cold weather. Scientists also suspect that Titan may have had active volcanoes, but that they spewed liquid water “lava” instead of molten rock.
(With inputs from solarsystem.nasa.gov)
