A rogue planet named Cha 1107-7626 has been observed in August 2025 exhibiting unprecedented growth by rapidly accreting about six billion tonnes of matter per second, blurring the lines between planets and stars.

This intense accretion event, the strongest ever recorded for a planetary-mass object, was driven by magnetic activity similar to stellar processes, with notable changes in the disc's chemistry, including the appearance of water vapor.

Findings suggest some rogue planets may form through mechanisms akin to star formation, involving contracting clouds of gas and dust, rather than solely from ejected planetary systems.

The growth process likely involves magnetic fields funneling material in a manner similar to star formation, although the precise triggers and mechanisms remain unclear.

The observed outbursts resemble EXor-type bursts seen in young stars, characterized by recurrent, short-lived increases in brightness, indicating Cha 1107-7626 may experience frequent accretion bursts.

Previous observations in 2016 also recorded high growth rate events, suggesting such accretion bursts could recur, prompting scientists to study their duration and frequency to understand their role in planetary development.

Despite its star-like growth behaviors, Cha 1107-7626 is not massive enough to sustain nuclear fusion, meaning it will eventually cool as it ages, but its growth process challenges traditional definitions of planets and stars.

While exhibiting star-like growth, Cha 1107-7626 remains a large planet in terms of mass, lacking the capacity for fusion, which emphasizes its unique position in planetary classification.

The observations, conducted by ESO's Very Large Telescope and supplemented by data from the James Webb Space Telescope, offer new insights into rogue planet formation and early planetary development.

Future telescopes like the Vera C. Rubin Observatory and the Nancy Grace Roman Space Telescope will improve the ability to study these faint objects, including their atmospheres and potential moons, advancing our understanding of their evolution.

The study, published in The Astrophysical Journal Letters, utilized a multi-instrument approach, combining data from ESO's VLT, JWST, and archival sources to analyze Cha 1107-7626.

The planet's rapid growth involved accreting about twice the mass of Lake Starnberg, highlighting the significant material intake during these bursts.

Rogue planets are free-floating objects not bound to stars, with estimates suggesting there could be trillions in the Milky Way, outnumbering stars by a ratio of 20 to 1.