Runaway World: Astronomers capture young rogue planet feasting on gas at record pace

An artist’s illustration depicts the planet Cha 1107-7626, situated roughly 620 light-years away from Earth. (Image: European Southern Observatory/L. Calcada/M. Kornmesser/Reuters)

Alone in the vastness of space, a young rogue planet has been caught in a furious feeding frenzy, offering rare clues about how such solitary worlds form and evolve.

What did astronomers find?
Researchers have identified a free-floating planet named Cha 1107-7626, estimated to be five to ten times the mass of Jupiter. The object was observed at the center of a swirling disk of gas and dust, drawing in material at a rate never seen before in a planet-sized body. During August this year, it devoured around six billion tonnes of material each second, nearly eight times faster than just a few months earlier.

“The outburst we detected is extraordinary,” said lead author Víctor Almendros-Abad from the INAF Astronomical Observatory of Palermo in Italy. “It shows that the same physical processes that shape young stars can also occur on a planetary scale.” The findings were published this month in The Astrophysical Journal Letters.

How young is the rogue planet?
Cha 1107-7626 is estimated to be about one to two million years old — extremely young by astronomical standards. Almendros-Abad noted that it appears to be nearing the end of its formation phase and is unlikely to gain much more mass. The team believes powerful magnetic fields are drawing gas from the surrounding disk toward the planet, a process previously observed only in stars.

Using the European Southern Observatory’s Very Large Telescope in Chile, the researchers captured the object located around 620 light-years away in the constellation Chamaeleon within our Milky Way galaxy.

How do rogue planets form?
Rogue planets, also called free-floating planetary-mass objects, are worlds not bound to any star. They typically have a mass several times that of Jupiter and drift freely through space. Their origins remain a mystery.

Study co-author Belinda Damian from the University of St Andrews in Scotland said such objects may form like stars—from the collapse of interstellar clouds—or like planets, within a disk around a young star before being ejected from the system.

Although Cha 1107-7626 is forming in a star-like way, it will never reach the mass required to ignite hydrogen fusion at its core. Similar objects, known as brown dwarfs, also fall short of becoming true stars but can briefly burn deuterium, a heavier form of hydrogen.

“This is a really exciting discovery because we often see planets as calm and stable,” Damian said. “Now we know they can be just as active as stars in their early years. It blurs the line between planets and stars and helps us understand how some rogue planets are born.”

(Inputs from Reuters)