Astronomers have made a remarkable discovery of a rogue planet, named Cha 1107-7626, which is consuming gas and dust at an unprecedented pace. Observations made using the European Southern Observatory’s Very Large Telescope (VLT) in Chile and the James Webb Space Telescope (JWST) reveal that this planet is currently the fastest-growing free-floating planet identified, gorging on materials at a staggering rate of 6.6 billion tons (6 billion metric tons) per second. The findings were reported on October 2, 2023, in The Astrophysical Journal Letters.
The study sheds light on the nature of rogue planets, which drift freely through space without the gravitational influence of a star. Many such planets have been discovered previously, but Cha 1107-7626 stands out due to its exceptionally rapid accumulation of material. Lead researcher Víctor Almendros-Abad, an astronomer at the Palermo Astronomical Observatory in Italy, emphasized that their investigation aims to determine whether these objects are remnants of planets ejected from their systems or if they formed independently from molecular cloud material, similar to stars.
Researchers identified an “accretion burst,” a phenomenon where a planet rapidly draws in significant amounts of surrounding material. While Cha 1107-7626 is continually accumulating matter, the team observed that its accretion rate fluctuates dramatically. Notably, in August 2025, the planet was observed to be accreting at a rate eight times faster than just a few months prior.
This behavior raises intriguing questions about the similarities between rogue planets and young stars. Accretion bursts have been well-documented in stars and play a vital role in their formation. Yet, the smaller size of rogue planets complicates the understanding of their formation processes. Co-author Alexander Scholz, a professor of astrophysics at the University of St. Andrews in Scotland, pointed out that while such bursts have been known since the late 1930s, the connection between accretion events and planetary mass objects like Cha 1107-7626 could indicate a universal mechanism behind these phenomena.
The discovery of rogue planets, including more than 500 identified by the JWST in the Orion Nebula, highlights the challenges of studying these elusive celestial bodies. They are difficult to detect because they emit infrared light, which requires advanced telescopes like the VLT and JWST to observe effectively. Almendros-Abad expressed hope that further observations with these instruments will enhance understanding of the formation processes of rogue planets.
As research continues, the team aims to determine the prevalence of accretion events among rogue planets. “Understanding how common these types of events are will provide insights into their evolution,” Almendros-Abad stated. The implications of this research extend beyond the immediate findings, offering a broader perspective on the formation of planetary systems and the nature of rogue worlds.
