The recent detection of numerous ‘rogue’ planets, including intriguing pairs dubbed “Jumbos,” by the James Webb Space Telescope has sparked curiosity among scientists. Now, a new study offers insights into the mystery surrounding these enigmatic celestial bodies.
For over two decades, astronomers have been intrigued by free-floating planets (FFPs), which lack a parent star and drift through space. Among them, pairs of Jupiter-sized worlds orbiting each other have particularly puzzled researchers.
A recent breakthrough study may provide clarity on the origins of these mysterious Jumbos. Led by Professor Dong Lai of Cornell University and Fang yuan Yu of Shanghai Jiao Tong University, the research investigates potential formation mechanisms for these intriguing planetary pairs.
One prevailing hypothesis suggests that Jumbos, along with FFPs in general, form from collapsing clouds of gas and dust, akin to miniature star formation. Another theory proposes that gravitational interactions with passing stars could strip these planets from their original stellar systems.
To explore these possibilities, Lai and Yu conducted tens of thousands of simulations of planetary systems containing Jupiter-mass planets orbiting sun-like stars. They found that Jumbos were more likely to form if the planets were initially orbiting closely together or if they were exceptionally massive, up to four times the mass of Jupiter.
Despite this, the likelihood of both planets being simultaneously ejected during a stellar flyby remained extremely low, less than 1%. In contrast, single planets were significantly more prone to being expelled, resulting in solitary FFPs.
The researchers’ findings, though yet to undergo peer review, have been submitted for publication in The Astrophysical Journal and are available as a preprint via arXiv. Lai and Yu’s research strengthens the plausibility of the cloud-collapse model for Jumbos formation.
Their study not only sheds light on the origins of these rogue planets but also holds implications for future astronomical observations. The simulations conducted by Lai and Yu are expected to aid in understanding planetary systems in dense star clusters and in identifying exotic configurations, such as captured planets.
In summary, this study marks a significant step forward in unraveling the mystery of ‘rogue’ planets, providing valuable insights into their formation processes and informing future astronomical research endeavors.
