These celestial bodies are slightly larger than Jupiter
Astronomers using the James Webb Space Telescope have detected six rogue worlds-cosmic objects that do not orbit stars. These celestial bodies are slightly larger than Jupiter and provide new insights into star and planet formation across the universe.
The Webb telescope observed the star-forming nebula NGC 1333, located 960 light-years away within the Perseus molecular cloud. This nebula's turbulence creates knots that collapse under gravity, leading to the formation of stars. Unlike the Hubble Space Telescope, which was hindered by dust, Webb's ability to observe in infrared light allowed it to see through the dust and capture detailed images.
Within the nebula, Webb identified newborn stars, brown dwarfs, and objects with planetary masses, all about five to ten times more massive than Jupiter. These findings highlight the existence of low-mass objects formed through processes typically associated with star formation, rather than planets or brown dwarfs.
The study, accepted for publication in The Astronomical Journal, explores the fundamental question of how light an object can form like a star. Ray Jayawardhana, senior study author and astrophysicist at Johns Hopkins University, noted that the smallest free-floating objects formed like stars are comparable in mass to giant exoplanets.
Lead study author Adam Langeveld, also an astrophysicist at Johns Hopkins, emphasized that these observations push the boundaries of understanding stellar and planetary formation, questioning if objects resembling young Jupiters could become stars under certain conditions.
The study confirms that planetary-mass objects can form in two distinct ways: from the contraction of gas and dust clouds, similar to stars, or from disks of gas and dust around young stars, as in the case of Jupiter in our solar system.
One newly detected object has a mass equivalent to five Jupiters, or about 1,600 Earths, and a surrounding dusty disk suggests it formed like a star. This raises the possibility that such planet-like objects might form their mini-planetary systems.
Aleks Scholz, study coauthor and astrophysicist at the University of St. Andrews suggested that objects with planetary masses could potentially form their planets, creating miniature planetary systems.
The Webb telescope also discovered a rare pair: a brown dwarf with a companion object of planetary mass, likely formed from a fragmenting cloud.
As researchers continue to study these rogue worlds, they aim to understand their formation and evolution. The upcoming NASA's Nancy Grace Roman Space Telescope, set to launch in May 2027, may further illuminate the nature of these wandering planets and help uncover the secrets of their existence.