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The vanishing “magical island” on Saturn’s largest moon Titan has intrigued scientists ever since it was discovered during a flight by NASA’s Cassini mission a decade ago. Researchers now believe they have uncovered the secrets of this phenomenon.
Temporary functionality was first thought of as: Made of bubbling gas bubblesBut astronomers now believe they are honeycomb-like glaciers made of organic material that fall onto the moon’s surface.
Scientists believe Titan is one of the most fascinating moons in the solar system because it shares some similarities with Earth. But in many ways, it also presents a puzzling and exotic landscape.
Titan is larger than the Moon or Mercury and is the only moon in the solar system with a thick atmosphere. The atmosphere is composed primarily of nitrogen and small amounts of methane, which gives Titan its hazy orange appearance. Titan’s atmospheric pressure is about 60 percent higher than Earth’s, creating pressures similar to those felt by humans swimming about 50 feet (15 meters) below the ocean’s surface. NASA.
Titan is also the only other world in our solar system with an Earth-like liquid body on its surface. But rivers, lakes, and oceans are made up of liquid ethane and methane, which form clouds and cause liquid gases to rain from the sky. .
of Cassini orbiter carrying the Huygens spacecraft It landed on Titan in 2005 and conducted more than 100 flybys of Titan between 2004 and 2017, revealing much of what scientists know about the moon today.
One of Titan’s most puzzling aspects is its magical island. Scientists observe them as moving bright spots on Titan’s ocean surface that can persist for hours, weeks, or even longer. Cassini’s radar images captured an unexplained bright region of Mare Ligeia, his second largest liquid body, on Titan’s surface. The ocean is 50% larger than Lake Superior and is made up of liquid methane, ethane, and nitrogen.
Astronomers considered these areas It could be a condensed bubble of nitrogen gas, an actual island made of suspended solids, or a feature attributed to waves (although the waves only reach a few millimeters in height).
NASA/JPL-California Institute of Technology
The artist’s illustration shows a lake at the north pole of Saturn’s moon Titan, including the raised rim detected by Cassini.
Planetary scientist Xin-Ting Yu, an assistant professor at the University of Texas at San Antonio, analyzed the connections between Titan’s atmosphere, liquid bodies, and solid material that falls like snow, and how they relate to the magical island. We focused on finding out whether there is a possibility that
“I wanted to investigate whether the magical islands could actually be organic matter floating on the surface of the earth, just as pumice can float on water on Earth and eventually sink.” said Yu, lead author of the study published Jan. 4 in the same journal. Geophysical Research Letters.
Scientists aim to understand as much as possible about Titan before sending a dedicated mission to the moon. The Dragonfly mission, led by the Johns Hopkins Applied Physics Laboratory in partnership with NASA, is expected to launch in 2028 and reach Titan in the 2030s.
Titan’s upper atmosphere contains a variety of organic molecules, including nitriles, hydrocarbons, and benzene. Surface temperatures were so low, minus 290 degrees Fahrenheit (minus 179 degrees Celsius), that rivers and lakes were carved out by liquid methane. This is how rocks and lava contributed to the formation of landforms and waterways on Earth.
Organic molecules in Titan’s atmosphere bond together in clumps before freezing and falling to the moon’s surface. Organic plains and dark dunes have been found across Titan, and scientists believe these formations were primarily created by Titan’s “snow.”
But what happens when hydrocarbon snow falls? On the eerily smooth surface of Titan’s liquid gas lakes and rivers? Yu and her colleagues investigated various scenarios that could occur.
Yu’s team determined that solid organic material falling from the upper atmosphere would not dissolve when it landed in Titan’s liquid body. This is because the liquid body is already saturated with organic particles.
NASA/JPL-California Institute of Technology/Stephane Le Moueric/Virginia Pasek
Infrared images taken by Cassini spacecraft’s instruments provide the clearest view of Titan from beneath the dense haze.
“For us to see magical islands, we can’t just float for a moment and then sink,” Yu said. “You have to stay afloat for a while, but not forever.”
However, liquid ethane and methane have a low surface tension, which means that solids are less likely to float on top of them.
Yu’s team simulated various models and found that frozen solid materials do not float unless they are porous, like a honeycomb or Swiss cheese. Also, small particles may not float on their own unless they are large enough.
The researchers’ analysis led to a scenario in which frozen hydrocarbon solids solidify near the coast, then break up and float across the Earth’s surface, much like Earth’s glaciers. Liquid methane slowly penetrates the frozen mass until it disappears from view.
Additionally, researchers say a possible thin layer of frozen solids in Titan’s oceans and lakes could explain why the moon’s liquid body is so smooth.
Over the next decade, dragonflies are expected to primarily explore Titan’s equatorial organic plains rather than liquids.
The rotary-wing lander will sample materials on Titan’s surface to study the potential habitability of its unique environment and determine what chemical processes are occurring on the moon.
Organic chemicals essential to life on Earth have also been found on Titan, such as nitrogen, oxygen, and other carbon-based molecules. Beneath Titan’s thick crust of ice is an inland sea of salty water, no different from other interesting oceanic world moons that orbit Saturn, such as Enceladus and Jupiter’s moon Europa. These moons are considered some of the best places to look for life beyond Earth.
Titan sounds inhospitable, but conditions there may be suitable for life, depending on different chemicals and forms, in ways beyond our current understanding. . NASA.