JWST reveals differences in dwarf planets' compositions

Scientists are using data from the James Webb Space Telescope (JWST) to learn more about tiny dwarf planets in the Kuiper Belt, a region beyond Neptune. This includes Pluto and Sedna, which have surprising differences in their surface chemistry. A new study reveals that Pluto has both methane and ethane on its surface, while Sedna, which is much smaller, has only methane. This difference could help scientists determine their masses. Lead author Amelia Bettati, from Elon University, says these icy worlds can provide insights into the early solar system. The researchers suggest that Sedna's smaller size results in weaker gravity. This weakness allows methane to escape into space over billions of years, while ethane remains. This study offers new clues about how different Kuiper Belt objects retain or lose chemicals over time. To support their findings, Bettati and co-author Jonathan Lunine analyzed the levels of methane and ethane on Sedna. They used similar objects like Comet 67P and Saturn’s moon Enceladus for comparison. Their models showed that while methane has escaped from Sedna, ethane has remained stable on both Sedna and Pluto. The research has implications beyond just Sedna and Pluto. For instance, another Kuiper Belt object called Gonggong also lacks surface methane, suggesting a similar loss process. Understanding how these gases behave helps scientists plan future space missions to explore these distant objects better. Overall, the study emphasizes how the JWST is changing our understanding of the farthest reaches of our solar system.