The James Webb captures a lonely object of the size of Jupiter devouring like a miniature sun

An international astronomer team has witnessed an extraordinary event: a lonely object, with a mass of just 5 to 10 times that of Jupiter, has entered a violent and prolonged growth burst. Using the combined power of James Webb Space Telescope (JWST) and him Vary Large Telescope (VLT) of the Southern European Observatory, scientists They have observed How this object, known as Cha J11070768-7626326, drastically increases its brightness and its “food” rhythm, behaving like a miniature star.

The importance. This discovery represents the first time that a outbreak of accretion of type “exor”, a phenomenon so far associated with young stars, in a body of planetary mass. The finding is not only a milestone in astronomical observation, but also further blur the borders between what we consider a giant planet and a small star.

The mystery. CH 1107-7626 is not a planet in the traditional sense that we all have in our mind. Although it has a mass comparable to that of a gaseous giant, I do not orbit any star and is 620 light years from the earth. Is what is known as an “free planetary mass object” or FFPMO (for its acronym in English). The existence of these lonely bodies raises a fundamental question for astronomy: are giant planets that were expelled from their solar systems, or are smaller stars that can exist in isolation?

In order to solve this enigma that astronomers have right now on the table, you have to analyze the gas and dust disc that is around, as well as the way of accumulating the material. The fact that Cha 1107-7626 has an album and feeds on it suggests that its origin is more like that of a star.

A cosmic feast. Astronomers observed Cha 1107-7626 in a state of calm in April and May 2025. However, for June, something had changed drastically. The object entered a “indulgence.” This means that its rhythm of ‘food’ began to increase, and in this way it reached a mass increase rate of 10-7 masses of Jupiter per year, the highest ever measured in a planetary mass object.

As a result of this frenzy, the objective became between 1.5 and 2 brighter magnitudes in visible light and its optical flow increased between 3 and 6 times. This outbreak remained active for at least two months, since it was still on the end of the observation campaign in August 2026.

But the most interesting thing is the speed it has. According to the observations made with the Vray Lark Telescope of the European Observatory, the growth rate is really aggressive, with a record rate of devouring 6,600 million tons per second of dust and gas.

Great footprints. Beyond the increase in brightness, the telescopes captured detailed physical changes that reveal the nature of the event. A hydrogen emission line, known as Hα, developed a “double peak” profile with a red displaced absorption. According to the authors, this profile is a “distinctive brand” of the accretion channeled through magnetic fields, a process called “magnetospherical accretion” observed in young stars.

But the most surprising finding was the change in the chemistry of the disc. At first, changes in the emission lines of the hydrocarbons molecules that came from the disc during the outbreak were seen. But water vapor also began to appear with a characteristic emission around 6.6 µm. This appeared during the outbreak where there was nothing before and is relevant because it is the first time that chemical changes of this type are observed caused by an increase in accretion.

Relevance. This event classifies Cha 1107-7626 as the first “exor” of known planetary mass. Exor outbursts are significant accretion events that are considered key episodes in the early evolution of the stars. They can deeply affect the physical structure and chemical composition of the protoplanetary disk, potentially influencing the early stages of planet formation.

Observing this process in such a small object demonstrates that the violent and fundamental mechanisms that the stars build also work at planetary scales. The study of Cha 1107-7626 offers an unprecedented vision of the accretion in the lower mass objects of the universe, providing a new window to understand how both smaller stars and the largest planets are formed.

Images | Javier Miranda

In Xataka | The most transformer of modern cosmology is just around the corner, according to the hypothesis of these physicists