Astronomers Detect Radio Emissions Directly From an Exoplanet for the First Time

Astronomers have directly detected radio emissions from a planet outside our solar system for the first time, providing the first direct measurement of an exoplanet’s magnetic field.

Radio signal detected from Beta Pictoris b

First discovered by astronomers using ESO’s Very Large Telescope in 2008, Beta Pictoris b is a gas giant exoplanet with a mass between nine and 13 times that of Jupiter.

The planet orbits its host star, Beta Pictoris, at a distance eight times greater than the distance between Earth and the Sun. The star has at least two planets and a circumstellar disk of gas and dust that could eventually evolve into a torus of icy bodies similar to the Kuiper Belt in our solar system.

The Beta Pictoris system is located approximately 63 light-years away in the constellation Pictor and is estimated to be only 23 million years old.

“As the most massive planet in the system, Pictoris βb has an angular spacing of up to 0.55 arcseconds throughout its 24-year orbit, and its host star is magnetically quiet, making the system an ideal target for radio observations,” said Kevin Ortiz Ceballos of Harvard University and the Smithsonian Center for Astrophysics.

Using the MeerKAT radio telescope array in South Africa, astronomers identified an auroral radio burst coming from Beta Pictoris b.

This discovery marks the first time radio emissions have been clearly traced to an exoplanet itself rather than to its host star.

What causes the exoplanet’s radio emissions?

Researchers believe the signal is produced by a mechanism called electron cyclotron maser instability. The same process causes auroral radio emissions from brown dwarfs and planets including Jupiter, Earth, Saturn, Uranus and Neptune.

“We believe that the radio emission is due to the coupling between Beta Pictoris b’s magnetosphere and ionosphere,” the researchers said.

Beta Pictoris b has a powerful magnetic field

Because the highest frequency of this type of radiation depends directly on the strength of the source’s magnetic field, the detection allowed scientists to calculate Beta Pictoris b’s minimum magnetic field strength.

The planet’s magnetic field is estimated to be around 1.25 kilogauss—thousands of times stronger than Earth’s magnetic field.

“This is the first direct measurement of the magnetic field strength of an exoplanet, and is consistent with dynamo-scale predictions for young, massive giant planets,” the researchers said.

The team’s paper, Discovery of Radio Emission from Exoplanet β Pictoris b, was published this month on the arXiv preprint server.

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Kevin N. Ortiz Ceballos et al. 2026. “Discovery of Radio Emission from Exoplanet β Pictoris b.” arXiv:2609.16720