On October 2, 2024, the James Webb Space Telescope (JWST) made a groundbreaking discovery by detecting traces of carbon dioxide and hydrogen peroxide on the surface of Charon, Pluto's largest moon. This finding is crucial for understanding Charon's surface and its origins.
Previously, in 2015, NASA's New Horizons spacecraft flew past Pluto and its moons, revealing that Charon's surface is covered with water ice. However, scientists had struggled to identify certain chemicals hidden at specific infrared wavelengths until the telescope helped fill these gaps.
According to Carly Howett, a scientist from the New Horizons mission who did not participate in the new study published in Nature Communications, "There are many chemical signatures here that we otherwise would not have seen." Scientists believe that hydrogen peroxide could have formed due to radiation reflecting off water molecules on Charon's surface. Carbon dioxide may have "spilled" onto the surface following impacts, as stated by co-author Silvia Protopapa from the Southwest Research Institute.
This discovery holds significant implications for studying Charon's origins and may aid in uncovering the compositions of other distant planets and their moons. Pluto, a dwarf planet, and its moons reside on the fringes of the Solar System in a region known as the Kuiper Belt. Alongside water ice, ammonia and organic compounds have previously been detected on Charon. Both Pluto and Charon are located over 3 billion miles (4.83 billion kilometers) from the Sun and are likely too cold to support life.