Observations by the James Webb Space Telescope have unveiled the presence of carbon dioxide and hydrogen peroxide on Charon, Pluto's largest moon. This marks the first detection of these substances on Charon's surface, which is about 750 miles (1,200 km) in diameter.
The findings, reported on October 7, 2024, indicate that Charon's surface also contains water ice, ammonia-bearing compounds, and organic materials. The presence of hydrogen peroxide suggests that the moon has undergone significant irradiation processes over its 4.5 billion-year history, while carbon dioxide is believed to have originated from primordial materials during Charon's formation.
Charon, discovered in 1978, is notable for being the largest moon relative to its planet in the solar system. The new data builds upon earlier observations made by NASA's New Horizons spacecraft during its 2015 flyby of the Pluto system.
Researchers utilized the Near-Infrared Spectrograph on Webb to conduct detailed observations, covering Charon's northern hemisphere. These discoveries contribute valuable insights into the evolution of celestial bodies in the outer solar system, highlighting the unique characteristics of each small body.