NASA Telescope Observes Interstellar Comet 3I/ATLAS Flare Exiting Solar System
The interstellar comet 3I/ATLAS has recently caught the attention of astronomers. NASA’s SPHEREx space telescope observed the comet dramatically brightening during its exit from the solar system. Notably, the observations occurred in December 2025, two months after the comet’s closest approach to the Sun.
Nasa Telescope Observes Interstellar Comet 3I/ATLAS Flare
The recent observations indicate that 3I/ATLAS experienced a significant increase in brightness and activity as it journeyed away from the Sun. This unexpected outburst released gas, dust, and complex molecules, providing crucial data about materials formed around other stars.
Key Observations from SPHEREx
- The comet developed a glowing coma rich in water vapor, carbon dioxide, and organic compounds.
- SPHEREx captured images revealing a pear-shaped dust tail created by rocky material ejected during heightened activity.
- 3I/ATLAS was observed actively releasing materials well after its perihelion, contradicting typical behavior for comets.
Carey Lisse, the lead author of the study, stated, “The comet was fully erupting into space in December 2025.” He emphasized that water ice was sublimating into gas, showcasing a chemical show unique to 3I/ATLAS.
Unique Characteristics of Comet 3I/ATLAS
Discovered in July 2025 by the ATLAS asteroid survey, 3I/ATLAS is only the third confirmed interstellar object to pass through the solar system. The previous objects were 1I/’Oumuamua in 2017 and 2I/Borisov in 2019. Unlike its predecessors, 3I/ATLAS allowed for an extended observation of its chemical composition.
SPHEREx operates in infrared light, enabling scientists to analyze a detailed mix of molecules released from the comet, including:
- Water ice
- Carbon dioxide
- Methane
- Methanol
- Cyanide
These substances are vital in the formation of celestial bodies, and the observations have led to new insights about the comet’s interior. Lisse noted that 3I/ATLAS released carbon-rich materials that had previously been locked beneath its surface.
Scientific Implications
The chemistry of 3I/ATLAS provides a unique opportunity to study and compare local comets with those formed around other stars. Understanding these similarities and differences could be pivotal in determining whether the essential raw materials for planets and life are widespread throughout the Milky Way.
Phil Korngut, a co-author of the study, remarked on the comet’s long journey through interstellar space. He noted that cosmic rays likely processed its crust, but as sunlight penetrated deeper, ancient ices began to release a mix of long-hidden chemicals.
The findings regarding comet 3I/ATLAS were published in February 2026 in the journal Research Notes of the AAS, marking a significant contribution to our understanding of interstellar objects and their role in our solar system.
