Astronomers have observed a young, free-floating planet undergoing an extraordinary growth spurt, consuming gas and dust at a staggering rate of 6 billion metric tons per second. This unprecedented growth, reported in the Astrophysical Journal Letters, offers valuable insights into the birth and evolution of rogue planets—planets that don’t orbit stars—and challenges existing theories about planetary formation.
Discovering Cha 1107-7626: A Unique Rogue Planet
The planet in question, named Cha 1107-7626, was initially detected roughly 20 years ago in the constellation Chamaeleon, located about 600 light-years from Earth. Estimated to be five to ten times the mass of Jupiter, Cha 1107-7626 was already a sizable object. However, recent observations reveal a period of intense growth unlike anything previously recorded for any planet, regardless of whether it orbits a star or drifts independently. Astronomer Victor Almendros-Abad from the Palermo Astronomical Observatory in Italy and his team sought to investigate how these rogue planets develop.
Unraveling the Mystery: Growth through Accretion
The team’s research aims to understand whether rogue planets form in a manner similar to standard planets around stars—essentially ejected from their original systems—or if they are born independently from collapsing clouds of gas and dust, similar to how stars are created. The current observations point toward the latter possibility.
Intense Growth and its Signatures
To study this process, the researchers utilized the Very Large Telescope (VLT) in Chile, analyzing ultraviolet, visible, and infrared light emitted by Cha 1107-7626 and the surrounding disk of gas and dust. Earlier-year observations showed expected growth, but late June’s data revealed a sudden and dramatic increase in accretion—the planet’s rapid intake of material.
- Rapid Material Intake: The rate of material accumulation increased eightfold within just a few months.
- Increased Temperature and Brightness: The planet’s surface and surrounding gas and dust became significantly hotter and brighter.
- Presence of Water Vapor: The disk surrounding the planet showed the presence of water vapor, which wasn’t detected in earlier observations.
Comparing the Planet’s Behavior to Young Stars
Notably, the prolonged duration of this gluttonous period—lasting from late June through August—mirrors the growth spurts observed in young stars. This comparison strengthens the possibility that Cha 1107-7626 may have originated from a star-like birth, further blurring the lines between planet and star formation. Evidence from 2016 also suggests that the planet regularly experiences these growth phases.
Future Observations and Their Importance
Astronomer Victor Almendros-Abad plans to continue monitoring the planet later this year to observe whether the intense accretion continues. One single event is not enough to fully understand the bigger picture, he acknowledges. The ultimate goal is to detect more rogue planets exhibiting similar growth spurts, allowing scientists to better understand the frequency and duration of these events, and ultimately refine our understanding of how rogue planets form and evolve. This research is crucial to broaden our perspective on planetary systems beyond our own and understand the diversity of planetary bodies in the galaxy
