By Jonny Lupsha, Wondrium Staff Writer
Saturn’s rings are shaped by the planet’s moons. Overall, Saturn has at least 62 moons of various orbital properties and physical characteristics that have been observed so far. A new NASA mission will visit Saturn’s largest moon, Titan.
NASA will launch the Dragonfly mission in 2027, which will send a proprietary quadcopter on a journey to document Saturn’s largest moon, Titan. It will take 10 years to reach its destination, where it will land and hop from spot to spot for three years gathering information with several scientific instruments. To better analyze the surface of the faraway moon, Dragonfly will use a gamma-ray and neutron spectrometer, a UV light, and a mass spectrometer.
Dragonfly won’t even start collecting data about the possible life-forming ingredients of Titan’s organic elements until 2037, but we already know a lot about Saturn’s moons. In her video series A Field Guide to the Planets, Dr. Sabine Stanley, Bloomberg Distinguished Professor in the Morton K. Blaustein Department of Earth and Planetary Sciences at Johns Hopkins University, said their study began in the 17th century.
Titan by the Numbers
“Titan really is in a class of its own amongst the Saturnian moons,” Dr. Stanley said. “Titan alone makes up 96% of the mass of all the moons and rings orbiting Saturn. Not only is Titan the largest moon of Saturn, [but] it’s also the only moon in the solar system with a substantial atmosphere.”
Dr. Stanley said that Titan’s atmosphere is about 98% nitrogen and 2% methane. By comparison, Earth’s is 78% nitrogen and 21% oxygen. Furthermore, the atmospheric pressure at Titan’s surface is 1.5 bars, which is equivalent to the pressure someone on Earth would feel swimming at 15 feet below the ocean surface.
“The atmospheric temperature at Titan’s surface is 94 Kelvin,” Dr. Stanley said. “Not cold enough for liquid nitrogen, but thanks to higher pressure, it’s cold enough for liquid methane. And, because of the low gravity on Titan, and small impact from the solar wind, this atmosphere can also extend much higher.”
A Popular Tourist Destination
Dragonfly will break plenty of new ground when it lands on Titan in 2037. For example, its quadcopter design will be the first of its kind in the outer solar system. However, it won’t be the first NASA mission to visit Saturn’s biggest moon.
“The Cassini mission also sent a probe through Titan’s atmosphere to land on the surface, taking observations there,” Dr. Stanley said. “The probe was named Huygens, after the person who discovered Titan. The Huygens probe traveled to the Saturn system attached to the Cassini spacecraft.
“Then on Christmas Day in 2004, the probe detached from Cassini and began making its way to Titan.”
After about three weeks, Huygens began its 2.5-hour descent onto Titan’s surface, becoming the first space probe to land on a moon in the outer solar system. Dr. Stanley said the surface began clearing at about 70 kilometers and Huygens began imaging the surface, capturing what appeared to be dry lake beds and networks of drainage channels that had been formed by liquid methane flowing on Titan’s surface.
“Huygens wasn’t our only opportunity for learning about Titan’s surface,” she said. “The Cassini spacecraft flew by Titan a total of 127 times during its mission, with a closest approach of 880 kilometers. Radar and infrared data were used to map the surface, and a geologically active world was revealed.”
Before long, humanity will have another chance to observe the large moon.