Rogue Planet Accretes at Unprecedented Rate of Six Billion Tonnes

Scientists have made a groundbreaking discovery regarding a rogue planet named Cha 1107-7626, which is accreting matter at an astonishing rate of six billion tonnes per second. This extraordinary growth was revealed through observations conducted using the European Southern Observatory’s Very Large Telescope located in Chile’s Atacama Desert. The findings indicate that the planet, roughly five to ten times the mass of Jupiter, is situated approximately 620 light-years from Earth in the Chamaeleon constellation.

The study, published in The Astrophysical Journal Letters, details a significant “growth spurt” for this free-floating planetary object, which does not orbit a star like the planets in our Solar System. Instead, it relies on a surrounding disc of gas and dust to fuel its rapid accretion process. Lead author, Dr. Victor Almendros-Abad from Italy’s National Institute for Astrophysics, stated, “This is the strongest accretion episode ever recorded for a planetary-mass object.”

Unprecedented Observations and Implications

Researchers observed that the rate of accretion for Cha 1107-7626 surged to six billion tonnes per second by August 2023, which is approximately eight times faster than earlier measurements. Professor Ray Jayawardhana from Johns Hopkins University expressed excitement over the discovery, saying, “We’ve caught this new-born rogue planet in the act of gobbling up stuff at a furious pace.” This level of activity suggests that the infancy of such planetary bodies may be more tumultuous than previously understood.

Co-author, Dr. Aleks Scholz from the University of St Andrews, highlighted the ongoing mystery surrounding rogue planets. “The origin of rogue planets remains an open question: are they the lowest-mass objects formed like stars, or giant planets ejected from their birth systems?” Scholz noted that the findings could indicate that some rogue planets share formation paths similar to stars, a notion supported by previous observations of young stellar bodies.

New Insights into Accretion Processes

The research team utilized the light emitted by the planet before and during the rapid accretion episode to gain insights into the dynamics of the surrounding disc. They found that magnetic activity may have significantly influenced the mass inflow, a phenomenon previously documented only in stars. This suggests that even low-mass objects like Cha 1107-7626 can possess strong magnetic fields that drive such massive accretion events.

Moreover, the study revealed that the chemistry of the disc changed dramatically during the accretion phase, with the detection of water vapour occurring only during this intense period. Professor Jayawardhana remarked, “We’re struck by quite how much the infancy of free-floating planetary-mass objects resembles that of stars like the Sun.” This discovery underscores the potential similarities between the formation processes of stars and rogue planets, implying that they may evolve from contracting clouds of gas and dust in a comparable manner.

In conclusion, the findings surrounding Cha 1107-7626 not only provide a unique perspective on the behavior of rogue planets but also invite further exploration into the nature of planetary and stellar formation. As researchers continue to investigate these elusive objects, the possibilities for understanding the universe’s diverse creations expand, raising intriguing questions about the origins of worlds beyond our own.