Somewhere in the Chamaeleon constellation, six hundred and twenty years ago, a small dark planet about the size of Jupiter began to do something planets are not supposed to be able to do. It started eating. The material — gas and dust from a disc surrounding it, the same kind of debris field that ordinarily surrounds young stars rather than young planets — began falling onto the planet’s surface at increasingly extreme rates. By the time light from the event reached the European Southern Observatory’s Very Large Telescope in Chile in mid-2025, the planet was consuming approximately six billion tonnes of gas and dust per second. The accretion rate had increased by approximately eight times in just a few months. The planet, in astronomical terms, was binge-eating at a rate that had never been observed in any planetary-mass object before. The European astronomers who detected the event published their findings in The Astrophysical Journal Letters in October 2025, and the object they had been observing — Cha 1107-7626 — became the most extreme example yet documented of an emerging class of cosmic objects that blur the boundary between what counts as a planet and what counts as a star.

According to the European Southern Observatory’s official announcement of the discovery, Cha 1107-7626 has a mass between five and ten times that of Jupiter, sits approximately 620 light-years from Earth, and does not orbit any star. It belongs to a category of objects called rogue planets, or free-floating planetary-mass objects, which drift through interstellar space without being gravitationally bound to a parent star. The object is young by astronomical standards — approximately one to two million years old, compared to the 4.6-billion-year age of our own solar system — and still in the active formation phase, surrounded by a disc of gas and dust from which it is continuing to grow. The lead author of the study, Víctor Almendros-Abad of the Astronomical Observatory of Palermo at Italy’s National Institute for Astrophysics, characterised the discovery directly: “People may think of planets as quiet and stable worlds, but with this discovery we see that planetary-mass objects freely floating in space can be exciting places.”

What the accretion event actually was

The technical phenomenon being observed is called accretion — the process by which a young astronomical object increases its mass by pulling in surrounding material from a circumstellar or circumplanetary disc. Accretion is well-characterised in young stars, which routinely accrete material from their surrounding discs at substantial rates during their formation phases. Accretion in young planets is far less well-documented, partly because planets are far harder to observe than stars and partly because conventional planetary-formation models did not predict that planet-sized objects would undergo accretion events of stellar-like magnitude. The Almendros-Abad team’s observations of Cha 1107-7626 represent the most extreme example yet documented of stellar-style accretion behaviour in an object that falls below the mass threshold for being classified as a star.

The X-shooter spectrograph mounted on the VLT detected a marked brightening of the object in mid-2025, accompanied by spectral fingerprints — specific patterns of light emission and absorption — that indicated infalling gas was hitting the planet’s surface and creating a bright hot spot. The team had previously observed Cha 1107-7626 in earlier months of 2025 at substantially lower accretion rates. The dramatic surge between roughly April-May and June-August 2025 took the accretion rate from approximately 750 million tonnes per second to approximately six billion tonnes per second — an eightfold increase over a period of just a few months. As reported by Phys.org’s coverage of the ESO findings, the event also produced detectable changes in the chemistry of the disc surrounding the planet, with water vapour appearing during the accretion episode but not before — a phenomenon that had previously been observed during accretion events in young stars but never in any planetary-mass object.

What the discovery actually means

The implications run substantially beyond the specific case of Cha 1107-7626. The conventional dividing line between planets and stars has been understood in terms of mass: objects below approximately 13 Jupiter masses cannot sustain even the limited form of fusion (deuterium fusion) that defines a brown dwarf, and are therefore classified as planets. Cha 1107-7626 sits comfortably below this threshold. But the accretion behaviour the European team observed — the magnitude of the infalling material, the apparent role of magnetic fields in funneling that material toward the planet’s surface, the formation of a hot spot at the point of infall, and the changing chemistry of the surrounding disc — all of these are features that astronomers had previously associated specifically with young stars, not with planetary-mass objects.

The team’s interpretation, summarised in the ESO announcement, is that planetary-mass objects can possess strong magnetic fields capable of powering stellar-like accretion events. This is a substantive shift in the understanding of how planets and stars relate to each other across the lower-mass end of the stellar-substellar spectrum. As reported by Space.com’s coverage of the discovery, Almendros-Abad described the implications in stark terms: “This is the strongest accretion episode ever recorded for a planetary-mass object.” The boundary between “small star” and “large planet,” in light of the Cha 1107-7626 observations, appears to be less clean than the previous mass-based classification system had suggested.

How rogue planets exist at all

The broader category of rogue planets — free-floating planetary-mass objects without any parent star — has been one of the more striking developments in modern astronomy over the past 25 years. The first confirmed rogue planet was identified in 2000. Since then, multiple surveys have estimated that the Milky Way may contain billions of such objects, with some studies suggesting that rogue planets may actually outnumber the stars in the galaxy. They form in two main ways, depending on which population is being examined. The first formation pathway involves direct gravitational collapse of a small fragment of an interstellar gas cloud — essentially the same process by which stars form, scaled down to substellar masses. The second pathway involves planets that originally formed around stars but were subsequently ejected from their planetary systems by gravitational interactions with other planets, typically during the chaotic early phases of system formation.

Cha 1107-7626 appears to belong to the first category. Its young age (approximately one to two million years), its retention of a surrounding accretion disc, and its location within a known star-forming region in Chamaeleon all suggest that it formed in place rather than being ejected from a parent system. The team’s observations of stellar-style accretion behaviour reinforce this interpretation: the object appears to be forming through a process structurally identical to the way young stars form, just at a substantially lower mass scale. Whether this means rogue planets like Cha 1107-7626 should properly be reclassified as a kind of failed star rather than as a kind of unbound planet is a question that the discovery is now actively reopening in the planetary-formation community.

What comes next

The 2025 observations of Cha 1107-7626 are unlikely to be the last word on the object or its kind. As documented by CBS News’s coverage of the discovery, the European Southern Observatory’s upcoming Extremely Large Telescope, currently under construction in the Atacama Desert of Chile, is expected to substantially improve the ability to detect and characterise rogue planets — which are typically faint, cold, and difficult to observe with current instruments. The combined capabilities of the ELT, the James Webb Space Telescope, and the next generation of ground-based interferometers should allow astronomers to identify additional accreting rogue planets, monitor their behaviour over multi-year periods, and assemble a substantially more complete picture of how planet-scale objects can form, grow, and evolve without ever being attached to a star.

What the Cha 1107-7626 observations have already established is that the universe contains objects that conventional planetary classification did not quite anticipate. A 5-to-10-Jupiter-mass body, drifting alone in interstellar space, eating six billion tonnes of gas and dust per second, exhibiting magnetic fields and accretion behaviour previously associated only with young stars — this is the kind of object that does not fit cleanly into the previous taxonomic categories. The 620 light-years of space between Earth and Cha 1107-7626 mean that the accretion event astronomers detected in 2025 actually happened approximately six centuries ago, around the time the European Renaissance was beginning. Whatever is happening at Cha 1107-7626 right now, in the present tense of the planet itself, will not be observable from Earth for another 620 years. By the time the light arrives, the object — assuming it continues growing at anything like its current rate — may no longer be a planet at all.