Astronomers using South Africa’s MeerKAT radio telescope have directly detected variable radio bursts from Beta Pictoris b, marking the first time a radio signal has been securely traced to a specific exoplanet. The 2025 and 2026 observations reveal a planetary aurora and provide a direct magnetic-field measurement.
Pinning Down a Faint Planetary Signal at 64 Light-Years
For decades, astronomers hunted for the radio crackle of worlds beyond our solar system. Those searches repeatedly came up empty. That changed when researchers used South Africa’s MeerKAT radio telescope array, situated 90 kilometers outside the Northern Cape town of Carnarvon, to observe the Beta Pictoris system across multiple sessions in 2025 and 2026. The massive gas giant exoplanet is located about 63 lightyears away. The South African MeerKAT radio telescope, situated 90 km outside the small Northern Cape town of Carnarvon, is a precursor to the Square Kilometre Array (SKA) telescope and will be integrated into the mid-frequency component of SKA Phase 1.
The breakthrough target, Beta Pictoris b, is a young gas giant roughly 10–12 times the mass of Jupiter, orbiting about 10 astronomical units from its host star—roughly the distance of Saturn from our sun. While previous observations found intriguing radio signals in planet-hosting systems, researchers could not prove whether the star or the planet generated them. To solve this, the team used nine quasars measured by Gaia and a precise radio calibrator as fixed reference points. By comparing the radio signal’s position against the mapped locations of the star and its planets, the researchers traced the emissions directly to planet b while ruling out both the star and neighboring planet c.
Aurorae, Rotation, and a Massive Magnetic Field
The detected signal is not a transmission from technological civilizations. Instead, the data reveal a natural planetary aurora driven by the electron cyclotron maser instability, or ECMI, where energetic electrons moving through a magnetic field generate intense radio waves. The emissions appeared as short bursts that brightened and faded rapidly across a broad frequency range, showing heavy circular polarization where the radio waves corkscrew through space. The signal showed up in rapid, recurring, and highly circularly polarised bursts
.
Because the highest frequency in an ECMI process depends directly on the local magnetic field strength, the bursts reaching 3.5 gigahertz—the upper limit of MeerKAT’s observing band—allowed researchers to establish a lower limit for the planet’s magnetism.
The analysis points to a field strength of at least 1,250 gauss at the emission site, compared to roughly half a gauss on Earth’s surface. Beta Pictoris b spins rapidly, completing a full rotation every eight to nine hours, with a full day lasting about eight hours.
Next Steps for Exoplanet Magnetism
Understanding planetary magnetic fields is critical for evaluating whether distant worlds can host life, because those fields shield atmospheres from being stripped away by stellar winds.
With this initial detection secured, researchers are already eyeing other nearby targets. According to findings published from Harvard & Smithsonian and University of Oregon researchers, seven other exoplanets across five solar systems close to Beta Pictoris are under consideration for follow-up examination. Whether next-generation instruments will achieve the required sensitivity upgrades to bring those fainter signals into focus remains the next major test for radio astronomy.
