Study: Saturn’s Moon Titan Has Huge Layer of Methane-filled Ice

2024 · VOA Learning English

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1. New research suggests Saturn’s moon Titan has a thick ice cover that could be warming lower areas and supporting molecular growth.

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2. Scientists at the University of Hawaii carried out the new study It appears in The Planetary Science Journal

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3. The findings add to existing evidence that Titan may hold the right mix of materials to support possible life.

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4. No life forms have been confirmed on Titan, a cold, icy world.

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5. But past studies suggest the moon now has a large layer of ice that once supported widely flowing water on the surface.

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6. Titan is also thought to contain a dense atmosphere rich in nitrogen and methane, both of which are found in Earth’s own atmosphere.

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7. NASA reports Saturn has a total of 146 moons orbiting it, more than any other planet.

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8. Titan, an ice giant, is the largest of them.

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9. For more than 10 years, NASA’s Cassini spacecraft studied Saturn “and its complex system of rings and moons,” the space agency said

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10. The new study used NASA data to closely examine surface details of Titan.

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11. The researchers used computer modeling to examine different elements of Titan’s surface.

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12. One of the main discoveries was that many craters examined on Titan’s surface were not as deep as some other moons.

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13. The team reported that in some cases, craters were hundreds of meters shallower, or less deep, than scientists expected.

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14. In addition, only 90 craters were identified on the whole moon.

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15. “This was very surprising because, based on other moons, we expect to see many more impact craters on the surface,” said University of Hawaii’s Lauren

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16. Schurmeier, who led the study. She said the research team had also expected to see much deeper craters.

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17. “We realized something unique to Titan must be making them become shallower and disappear relatively quickly,” she said.

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18. Computer modeling carried out by the researchers showed how the surface might have changed to remove signs of major impact craters.

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19. The researchers said one of the most likely causes of such change was that the moon’s icy surface is covered with a thick layer of solid water ice, with methane

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20. The team said the data examinations suggest Titan has a methane-filled icy crust that is from five to 10 kilometers thick.

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21. The modeling operations run by the scientists produced images that looked similar to crater formations on Titan’s surface.

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22. Schurmeier said the methane crust, “warms Titan’s interior” and can cause surprisingly fast changes to the surface structure.

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23. Schurmeier noted, for example, that crater shallowing on Titan is believed to be happening at a rate “that is close to that of fast-moving warm glaciers on Earth.”

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24. Because of this extreme cold, liquids on the moon’s surface take the form of ice, with methane gas locked inside, the researchers said.

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25. This gas could help warm surface levels beneath, possibly permitting molecules to rise toward the surface.

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26. Schurmeier said studying the thickness of Titan’s icy crust is important because it might help explain how the moon’s atmosphere began to develop.

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27. The measurements could also provide additional information on Titan’s changing climate.

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28. “Titan is a natural laboratory to study how the greenhouse gas methane warms and cycles through the atmosphere,” she said.

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29. The resulting information, she added, can provide important insights about such processes happening on Earth.

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30. NASA’s Cassini spacecraft ended it mission in 2017, when it crashed into Saturn’s atmosphere. But the U.S.

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31. space agency has plans to send another explorer to Titan in 2028.

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32. That mission calls for a spacecraft called Dragonfly to travel to Titan to observe many different areas.

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33. The planned explorer, called a rotorcraft, operates similar to a helicopter. I’m Bryan Lynn.

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