The VLA radio telescope in New Mexico listened to the sky for two sessions of 96 minutes each and caught short radio bursts from the object 2M2228—a brown dwarf. This cosmic body is heavier than a planet but lighter than a star: thermonuclear reactions never ignite in its core, so it simply cools over time. The flares arrived with intervals of 47 minutes during the first session and 58 minutes during the second.

The signal turned out to be strongly polarized — the radio waves oscillated predominantly in one direction, as if they had passed through a grid. Such behavior is typical of radiation from electrons spiraling around magnetic field lines. From the strength of the flares, astronomers estimated the dwarf's magnetic field: it is no weaker than 1.4 kilogauss — hundreds of times stronger than Earth's magnetic field. The researchers suspect this is the same mechanism that produces auroras on Jupiter, but much more powerful.

The observations are still short, and the flare periods may be refined. But it is already clear that 2M2228 is a convenient target for future coordinated observations with radio telescopes and the James Webb Space Telescope. This could test whether the radio flares are linked to weather in the brown dwarf's atmosphere and how its magnetic field drives the auroras.