Home / Science / Interstellar Comet's Changing Colors Hint at Hidden Core
Interstellar Comet's Changing Colors Hint at Hidden Core
17 Apr
Summary
- Interstellar comet 3I/ATLAS's chemistry changed near the sun.
- Its coma's gas ratio differs from its internal ice composition.
- Study offers insights into planet formation in other star systems.
The interstellar comet 3I/ATLAS, one of only three such objects detected passing through our solar system, is revealing clues about planetary formation in other star systems. Scientists observed changes in its chemical composition as it neared the sun on October 29, 2025. Using the Subaru Telescope, researchers analyzed the comet's coma, the gaseous envelope surrounding it.
The study found that the ratio of carbon dioxide to water in 3I/ATLAS's coma had altered. This change indicates that the comet's internal chemistry is distinct from its external layers. This finding provides a unique opportunity to compare the materials present in other solar systems with those in our own.
As more interstellar objects are expected to be discovered, studies like this one will deepen our understanding of how planets form across diverse stellar environments. The research, with a peer-reviewed version available on arXiv, is slated for publication in The Astronomical Journal on April 22, 2026.
