Kathrine Frich
A rare visitor from beyond the Solar System has given scientists a fleeting chance to peer into the chemistry of deep space.
As it swept past the Sun and Earth, the object left behind more than a glowing trail.
An unusual scientific opportunity
American researchers studying observations from NASA’s SPHEREx space telescope say the interstellar comet 3I/ATLAS discharged significant quantities of organic compounds during its close approach to Earth in late 2025.
The team reports that substances including methanol, cyanide and methane were detected in the material expelled from the comet.
These chemicals are linked to biological activity on Earth, although scientists note they can also arise through non-biological reactions.
According to NASA, the comet offered an unusual scientific opportunity.
After skimming close to the Sun and reaching its nearest point to Earth in December 2025, frozen material beneath its surface was exposed and released into space.
Sudden outburst
Carey Lisse of Johns Hopkins University, who led the latest study, described the dramatic event in a press release:
“Comet 3I/ATLAS literally exploded into space in December 2025, also releasing water that quickly turned to gas. The emission of new, carbon-rich material was exceptionally abundant.”
Beyond volatile gases, researchers identified soot and rocky dust in the debris cloud, elements commonly associated with cometary bodies.
Lisse added:
“We’re observing the full range of material from the early solar system, including organic compounds, soot, and rock dust that would normally be released from a comet.”
Long cosmic journey
First spotted in July 2025, 3I/ATLAS was traveling at roughly 221,000 km/h within Jupiter’s orbit.
Astronomers believe it has wandered through interstellar space for billions of years.
Its speed is thought to have increased through repeated gravitational interactions with stars and nebulae, a process often compared to a slingshot effect.
The comet is now heading toward Jupiter. Scientists hope NASA’s Juno spacecraft may capture further observations before the object exits the Solar System, possibly for good.
Members of the SPHEREx team have described the chance to examine such an interstellar traveler so early as a fortunate break for planetary science.
Sources: NASA, Johns Hopkins University, WP.
