Cha 1107-7626 is a runaway planet that eats like a star: it grows at a speed never seen before, devouring gas and dust as if starving for matter.
Deep in the constellation Chameleon, about 620 light-years away, astronomers have identified a lonely world that defies all known logic. It’s called Cha 1107-7626, a wandering planet that appears to be growing at a rate never seen before, devouring gas and dust as if starving for matter.
Instruments at the Very Large Telescope in Chile and the James Webb Space Telescope have recorded an impressive pace: nearly six billion tons of material per second, a rate that makes it the fastest-growing planetary-mass object ever discovered.
Lonely. This planet does not orbit around any star, but wanders in space, immersed in a cloud of gas that seems to power it like a miniature star. The researchers, led by Víctor Almendros-Abad of the Palermo Astronomical Observatory, observed a sudden explosion of accretion, a “burst” during which Cha 1107-7626 began to absorb matter eight times faster than usual.
Anomaly. The event surprised scientists, because these accretion flashes are typical phenomena of young stars, not planets, and could reveal that the boundaries between the two categories are more blurred than previously thought.
Co-author Alexander Scholz, an astrophysicist at the University of St. Andrews, explained: “These sudden increases in brightness, known since the 1930s, play a key role in the birth of stars, heating gas clouds and shaping the environment in which new worlds are born. The fact that a solitary planet can exhibit the same behavior suggests that perhaps a universal mechanism exists, capable of governing the growth of both stars and planets.”
Unique. Cha 1107-7626, which has an estimated mass between five and ten times that of Jupiter, is enveloped in a disk rich in water vapor and hydrocarbons, a chemistry strikingly similar to that of young stars.
According to the researchers, this could mean that the lone planet formed independently, by the gravitational collapse of a cloud, rather than as a planet ejected from its home system. The discovery opens a new window on the universe of wandering planets, bodies that do not belong to any star and that glow faintly in infrared light.
How is a star born? In recent years, the James Webb telescope has identified more than five hundred of them in the Orion Nebula, but Cha 1107-7626 remains a unique case, because it shows dynamic, almost vital behavior, as if it were a young star in search of its own identity.
Astronomers will continue to observe it, hoping to understand whether these bursts of accretion are common or whether Cha 1107-7626 is truly a cosmic exception. Each new observation could bring us closer to a fundamental answer: where does a planet end and a star begin?
