Rogue planet Cha 11077626 undergoes strongest accretion burst

Astronomers have observed a freefloating planet about 620 light years from Earth undergoing a monthslong growth spurt, accreting gas and dust at a peak rate of roughly 6 billion tonnes per second, the strongest such episode recorded for any planetarymass object. The observations, led by Víctor AlmendrosAbad and published October 2 in The Astrophysical Journal Letters, tracked the object known as Cha 11077626 in the Chamaeleon constellation as its accretion rate rose sharply through mid 2025 and reached a sustained peak by August.

Cha 11077626 has an estimated mass of five to 10 times that of Jupiter and is embedded in a rotating disc of gas and dust from which it draws material through the process known as accretion. The research team began monitoring the object with the European Southern Observatory’s Very Large Telescope in April and recorded an increase in the flow of matter that grew to about eight times the earlier rate over a few months. Data from the James Webb Space Telescope and other instruments supplemented the VLT measurements.

“This is the strongest accretion episode ever recorded in a planetarymass object,” AlmendrosAbad said, describing the unprecedented intensity...