MeerKAT telescope detects direct radio signals from Beta Pictoris b
Astronomers using the MeerKAT radio telescope array in South Africa have detected direct radio emissions originating from the gas giant exoplanet Beta Pictoris b. The observation marks the first time that radio signals from beyond the Solar System have been definitively pinpointed to an exoplanet rather than its host star.
The detected signals, recorded across frequencies between 0.85 and 3.5 GHz, revealed a magnetic field of at least 1,250 gauss, or 1.25 kilogauss, at the planetary emission site. Lead author Kevin N. Ortiz Ceballos stated in the study that “no radio detection has previously been unambiguously localized to an extrasolar planet rather than its host star.”
Astrometric alignment confirms planetary origin
To establish that the signals originated from the exoplanet rather than the nearby host star, the research team aligned the MeerKAT radio images with distant background quasars used as fixed astrometric reference points. The resulting analysis demonstrated a statistical significance of 4.4 sigma against the host star position, confirming that the radio source physically moves alongside Beta Pictoris b. This high-precision technique solved a persistent problem in radio astronomy, where wide instrument beams previously failed to resolve the narrow spatial separation between young stars and their orbiting companions.
The observations were conducted at the MeerKAT facility, situated near Carnarvon in the Northern Cape region of South Africa. The data collected by the instrument array showed both continuous radio emission and rapid, recurring pulses characterized by high circular polarization. These pulses repeat at intervals of 8 to 9 hours, directly matching the rotation period of the gas giant as it spins on its axis.
Electron cyclotron maser instability generates auroral radio beams
The detected transmissions do not have an artificial or biological origin. Astrophysical analysis shows that the radiation is entirely natural, produced in the upper atmospheric layers of Beta Pictoris b by a process known as electron cyclotron maser instability. Under this mechanism, charged particles accelerate along planetary magnetic field lines toward the poles, interacting with the surrounding plasma to generate coherent, beamed radio waves that create powerful polar auroras.
Read also: Hubble telescope detects ten-sided wave at Saturn’s pole
Beta Pictoris b is a young gas giant with an estimated mass between 10 and 12 times that of Jupiter. The planetary system is located between 63 and 64 light-years from Earth, offering astronomers a nearby laboratory to study planetary formation and magnetospheric activity. The minimum field intensity of 1,250 gauss measured at the polar emission site indicates a magnetosphere significantly stronger than that of any planet within the Solar System.
Technical metrics recorded by the MeerKAT array
The multi-frequency datasets collected during the campaign provided detailed physical parameters regarding the planetary environment and the geometry of its radiation:
- Emission frequency range: 0.85 to 3.5 GHz across continuous and pulsed regimes.
- Minimum magnetic field strength: 1,250 gauss at the altitude of auroral generation.
- Planetary mass: 10 to 12 times the mass of Jupiter.
- Rotational period: 8 to 9 hours between pulse peaks.
- System distance: 63 to 64 light-years from Earth.
- Positional certainty: 4.4 sigma statistical separation from the central star.
Significance of magnetic field measurements for planetary evolution
Within the Solar System, Earth and the four giant planets routinely produce coherent auroral radio emission through similar electrodynamic processes. Measuring these fields beyond our planetary system has remained an elusive goal for decades because stellar activity often masks the weaker planetary signals. Magnetic fields act as shields against stellar winds and high-energy radiation, dictating how planetary atmospheres retain volatile gases or erode over time.
Keep reading: Astronomers record strong cosmic emission from 8 billion light years with MeerKAT radio telescope
Commenting on the broader implications of the findings, Suzanne Aigrain, professor of astrophysics at the University of Oxford, noted the relevance of the breakthrough. “Astronomers have been looking for radio signals from exoplanets for some time. There have been tentative, indirect detections before, but this is the first truly convincing direct detection, and it hopefully paves the way for many more,” said Aigrain.
Status of the research and upcoming evaluations
The study was conducted by Kevin N. Ortiz Ceballos and Edo Berger of the Center for Astrophysics | Harvard & Smithsonian, alongside Yvette Cendes of the University of Oregon. Ortiz Ceballos submitted the scientific paper to the arXiv preprint repository on September 15, 2026. The research community began broader discussion of the results following technical coverage on Tuesday (22) and Wednesday (23), followed by additional reporting on Thursday (24).
Formal acceptance and final publication in a peer-reviewed scientific journal remain pending while the manuscript completes the standard academic evaluation process.
