James Webb telescope finds first possible brown dwarfs outside the Milky Way
The James Webb Space Telescope (JWST) may have discovered brown dwarfs – known as ‘failed stars’ – outside our Milky Way for the first time. This finding offers a fresh look at star formation and conditions in the early universe. Brown dwarfs are unusual. They are larger than planets, but smaller than stars. These objects form in a manner similar to stars, collecting gas and dust, yet lack the mass needed to ignite nuclear fusion. This makes them look dim, cold and star-like, but without the light and energy of real stars. Typically, brown dwarfs weigh between 13 and 75 times the mass of Jupiter, making them larger than most planets but less powerful than stars.
A closer look at NGC 602
Using its near-infrared camera, JWST focused on a young star cluster, NGC 602, located in the Small Magellanic Cloud (SMC), one of our galaxy’s nearest neighbors. Within this star cluster, researchers have identified approximately 64 objects that may qualify as brown dwarfs. Each has a mass between 50 and 84 times that of Jupiter. This places brown dwarfs in a star cluster outside our Milky Way for the first time. It creates an important breakthrough for astronomers.
Why this discovery is important
This cluster, NGC 602, has a composition similar to that of the early universe. It contains fewer elements heavier than hydrogen and helium, reflecting conditions before later stars enriched the cosmos with heavier elements. Study these metal-poor brown dwarfs could reveal why certain stars don’t ignite, adding another layer to our understanding of cosmic evolution. This discovery could also explain why brown dwarfs are so common in the Milky Way, and may even be larger than the stars themselves.
Unlocking the secrets of star formation
NGC 602 offers a unique opportunity to investigate star formation under conditions similar to the early days of the universe. This breakthrough could bring us closer to understanding how stars and planets formed in the harsh, early universe.
