Astronomers Detect First Radio Emission From Exoplanet Beta Pictoris b

Astronomers have identified repeating radio bursts that appear to originate from Beta Pictoris b, a gas-giant planet about 12 times the mass of Jupiter and located 63 light-years from Earth. The signal, captured with the MeerKAT array in South Africa, is interpreted as auroral radio emission generated by an exceptionally strong planetary magnetic field.

"I know radio signals are associated with searches for extraterrestrial intelligence, but this is something very different," said Edo Berger, a Harvard University professor of astronomy.

Berger and colleagues explain that the observed frequencies require a magnetic field at least 200 times stronger than Jupiter's, producing auroras similar to Earth's northern lights but on a far larger scale. The detection marks the first time such emission has been unambiguously linked to an exoplanet rather than its host star.

"What is unique for this study is that they localise the emission to the planet itself, separate from the star," noted Joseph Callingham, an associate professor at the University of Amsterdam who was not involved in the work.

The finding could provide a new method for probing exoplanet interiors and atmospheres, as radio observations reveal properties otherwise inaccessible. If the results withstand peer review, they would suggest that some exoplanets possess magnetic fields far exceeding those of planets in our solar system, offering a novel laboratory for testing magnetospheric theories.

"Auroral radio emissions are important because they allow us to understand how an object interacts with its local space environment," said Jonathan Nichols, a planetary aurora specialist at the University of Leicester.

The research team plans additional telescope observations to confirm the signal and investigate why Beta Pictoris b’s magnetic field is so intense. The paper is currently posted on the preprint server arXiv and is undergoing peer review.