Astronomers may have directly detected auroral radio emission from a planet outside our solar system for the first time. The candidate signal comes from Beta Pictoris b, a young gas giant roughly 63 light-years away, picked up by the MeerKAT radio telescope array in South Africa. The research, led by Kevin N. Ortiz Ceballos and collaborators at the Center for Astrophysics, Harvard and Smithsonian, and the University of Oregon, was posted to arXiv on September 15, 2026, and has not yet undergone peer review.
What MeerKAT Heard
The detection rests on a distinctive radio signature that physicists recognize as a direct imprint of a planetary magnetic field.
MeerKAT’s 64 antennas recorded both rapid, recurring bursts and persistent radio emission across a frequency range of 0.85 to 3.5 gigahertz. The signal showed high circular polarization, consistent with electron cyclotron maser emission: coherent radio waves produced when energetic electrons spiral along magnetic field lines.
That process is well understood on Earth and Jupiter, where it drives auroral radio activity similar in principle to the northern lights. There it generates some of the most intense natural radio signals in the solar system.
The highest detected frequency implies a minimum magnetic field strength of approximately 1,250 gauss at the emission site. Earth’s surface field runs around 0.5 gauss, while Jupiter’s reaches roughly 14 gauss in its strongest regions. Beta Pictoris b, on this preliminary measurement, dwarfs both by a wide margin at the radio-emitting region.
The team’s preprint states directly: “Here, we report the first direct detection of auroral radio emission from an exoplanet, the giant planet Beta Pictoris b, with the MeerKAT array.”
Why This Detection Is Different
Localizing the emission to the planet rather than its host star is what sets this result apart from every prior exoplanet radio search.
A planetary magnetic field generates a magnetosphere, a region that deflects charged particles streaming from the host star. On Earth, that shield contributes to keeping the atmosphere stable over geological time, alongside gravity, atmospheric chemistry, and other factors. Detecting one around an exoplanet is relevant to long-running questions about habitability, though Beta Pictoris b itself is a massive, hot gas giant with no solid surface.
Discovered through direct imaging in 2008, Beta Pictoris b is roughly 12 times Jupiter’s mass and located about 63 light-years away. It is approximately 20 to 25 million years old, young enough that residual internal heat may be fueling an unusually powerful magnetic dynamo.
Unlike earlier radio searches that returned ambiguous results or no detection at all, MeerKAT’s interferometric design allowed the team to spatially separate the planet’s signal from its far brighter host star. That localization is the core distinction between this result and prior attempts.
Observations ran through 2025 and early 2026, with follow-up sessions in May 2026. The 3.5-gigahertz upper observing limit means the 1,250-gauss figure is a lower bound at the emission region. It is not a complete map of the planet’s global field.
Peer review and independent follow-up observations will determine whether the detection holds. If confirmed, the result would establish the first direct magnetic-field strength measurement for any planet beyond our solar system. It would also open a new observational tool for characterizing distant worlds. Extending the method to smaller, rocky planets will require considerably more sensitivity. Their weaker fields and denser atmospheres may eventually demand space-based or lunar far-side radio facilities.
