A team of astronomers has made a groundbreaking discovery by observing the radiation belt around a dwarf star outside our solar system. This is the first time such an event has been observed outside our own planetary system. The radiation belt was detected around a very cool dwarf star about 18 light-years from Earth. This discovery is particularly interesting because the radiation belt around this dwarf star is similar in structure to the radiation belt around Jupiter. But it seemed about 10 million times brighter.
The radiation belt consists of high-energy particles trapped by the magnetic field of the dwarf star, known as LSR J1835+3259. Through advanced imaging techniques, astronomers were able to visualize a cloud of high-energy electrons confined within the star’s magnetic field. This region is referred to as the magnetosphere and emits intense radio radiation. By observing this emission, the researchers were able to image the magnetosphere, a groundbreaking achievement essentially.
The team used a network of 39 radio telescopes that work in unison. The system effectively creates a virtual telescope called a ‘High Sensitivity Array’. This technique allowed them to capture an image of the radiation belt surrounding LSR J1835+3259. Melody Kao, lead researcher at the University of California, San Francisco, explained the significance of the observation, noting that this has not been done for any object outside our solar system.
The dwarf star LSR J1835+3259 was chosen for this study because of its size and location. It falls into the category of low-mass stars and brown dwarfs, often called “failed stars” because their cores lack the mass required to initiate nuclear fusion. New observations of this star’s radiation belt may help astronomers define the boundary between small stars and large planets. The publication of this research in the journal Nature marks a significant milestone in our understanding of the radiation belt and magnetosphere outside our solar system.