On December 24, 2024, researchers utilizing NASA's James Webb Space Telescope (JWST) reported groundbreaking findings about Chiron, a centaur located between Jupiter and Neptune. This hybrid object exhibits characteristics of both asteroids and comets, offering new insights into the solar system's early history.
The study, led by Dr. Noemí Pinilla-Alonso from the University of Oviedo and Dr. Charles Schambeau from the University of Central Florida (UCF), highlights Chiron's dual nature. The research revealed that Chiron's surface contains both carbon dioxide and carbon monoxide ice, while its coma—a cloud-like envelope surrounding the object—contains these materials in gas form, along with methane. This marks the first detection of such chemical diversity in a centaur.
Dr. Pinilla-Alonso emphasized that Chiron acts as a "time capsule," preserving information about the solar system's formation. The unique characteristics of Chiron allow scientists to observe both its surface and coma, providing critical data about its ice layer's thickness, porosity, and chemical properties.
Chiron's activity, primarily driven by solar heating, enables researchers to study its surface chemistry even at great distances from the Sun. This capability is particularly significant as it offers clearer insights compared to other trans-Neptunian objects (TNOs), which are usually less active at such distances.
The research team plans to continue monitoring Chiron as it approaches Earth, aiming to understand how its features respond to variations in sunlight and temperature. Dr. Pinilla-Alonso noted that centaurs like Chiron typically are ejected from the giant planets region after about one million years, potentially evolving into Jupiter Family comets or returning to the TNOs region. Future observations may further illuminate the processes that shaped our solar system over billions of years.