Researchers stunned after spotting rogue planet, Cha 1107-7626, growing at 6 billion tons per second

Adolescents have growth spurts that can leave them unrecognizable in a year, but ever heard of a planet with this experience? A team of astronomers has witnessed it and published the insights in The Astrophysical Journal Letters. The planet in question is Cha 1107-7626, and its growth spurt is apparently something that has never been noted before in a free-floating planet. Another noteworthy aspect was that it behaved more like a star than a planet. This extraterrestrial body is located outside the solar system, around 620 light-years from Earth in the Chamaeleon constellation. 

One-of-a-kind

The Cha 1107-7626 stands apart from other planets in different ways, according to CNN. According to estimates, its mass could be five to ten times more than Jupiter, the largest planet in the solar system. Furthermore, the interstellar planet is getting bigger every day, with a growth spurt like no other. Aleks Scholz, an astronomer at the University of St. Andrews in Scotland and a study co-author, shares that the planet is around one to two million years old, which, astronomically speaking, implies it is still in its infancy. Unlike the planets in the solar system, Cha 1107-7626 does not orbit any star.  The observations used in the study have been gathered through the European Southern Observatory's Very Large Telescope (VLT) in Chile's Atacama Desert, as well as the James Webb Space Telescope (JWST).

These observations indicated that the planet is always enveloped by a disk of gas and dust. This disk is incorporated within the planet, with a process called accretion, which enables it to grow. Researchers have yet to determine the rate of this growth, and believe that it is constantly changing. Recent readings revealed that Cha 1107-7626 is adding material eight times faster than it did some months earlier in 2025 and achieved a record rate of accretion of around 6.6 billion tons (6 billion metric tons) per second. Lead study author Víctor Almendros-Abad, an astronomer at the Palermo Astronomical Observatory of the National Institute for Astrophysics in Italy, claims this is the strongest growth rate ever recorded for any planet.

Origin of the rogue planets

Because Cha 1107-7626 is not orbitally bound to any star, it becomes a "rogue planet." Such planets have been noted before, but remain elusive in terms of their nature. Researchers are hopeful that analysis of bodies like Cha 1107-7626 will reveal more insights about the origin of rogue planets, according to the European Southern Observatory (ESO). Scholz is hopeful that further examination can shed light on whether a rogue planet is formed like a star or ejected out of the system of a giant planet. 

Based on the data gathered until now, the team believes that rogue planets have more similarity with stars in terms of formation, as both bodies exhibit bursts of accretion. "This discovery blurs the line between stars and planets and gives us a sneak peek into the earliest formation periods of rogue planets," Belinda Damian, also an astronomer at the University of St Andrews, shared. 

Spotlight on accretion process

The most pivotal observation undertaken during the evaluation was Cha 1107-7626's record-breaking accretion. Therefore, experts concentrated a lot on this process and collected some crucial insights. The nature of magnetic activity played a part in the way mass accumulated on the planet. Such a relationship has been observed only in stars before, further backing the assertion that there are similarities between star and rogue planet formation. The findings also highlight that even low-mass objects, like a rogue planet, are capable of exhibiting strong accretion.

Another feature that the team recorded was that the chemistry of the disc surrounding the planet changed before and during the accretion. Water vapor was spotted in the disc during the accretion, but not before it. Again, this phenomenon has been detected before in stars, and not planets. Such similarities are intriguing for experts. "The idea that a planetary object can behave like a star is awe-inspiring and invites us to wonder what worlds beyond our own could be like during their nascent stages," co-author and ESO astronomer Amelia Bayo shared. Researchers are hopeful that more of these faint rogue planets will soon be available for examination, with the advanced technology of ESO's upcoming Extremely Large Telescope (ELT).