Astronomers Detect Radio Signals From an Exoplanet for the First Time
Researchers from Harvard and the University of Oregon, using the MeerKAT radio telescope in South Africa, have unambiguously traced a radio signal directly to an exoplanet — the gas giant Beta Pictoris b — for the first time. The team stresses the emission has a natural origin, not extraterrestrial life.
About 63 light-years from Earth lies the Beta Pictoris system, a planetary system less than 1 percent as old as our own solar system. It contains a star more massive than the sun, three giant planets, and a vast disk of dust and debris.
A new study by researchers from Harvard and the University of Oregon reports that one of these worlds, Beta Pictoris b, is the first exoplanet from which radio waves have been definitively traced. The signal was recorded by the MeerKAT radio telescope in South Africa.
Beta Pictoris b is a gas giant several times more massive than Jupiter, only tens of millions of years old, making it extremely young by astronomical standards. It orbits at a distance from its star comparable to the distance between the sun and Saturn, which allows it to be observed separately from the star's glare.
A natural signal, not aliens
The study's authors, whose work has not yet been peer-reviewed, immediately note that the signal is most likely of natural origin rather than evidence of extraterrestrial life. They present substantial evidence pointing to intense magnetic activity as the source of the radio emission.
The characteristics of the detected radio waves match theoretical predictions for magnetic fields generated by young, massive planets. Charged particles can become trapped in a planet's powerful magnetic field, and as the planet rotates, these particles accelerate and release energy as radio waves — a phenomenon known as auroral radio emission.
The team detected several such signals and, for the first time, managed to pinpoint their origin directly to an exoplanet, a goal researchers have pursued for years.
In 2023, scientists came close to a similar finding when radio bursts were detected in the YZ Ceti system, appearing to repeat in sync with a planet's orbit, though they could not rule out that the star itself caused the emissions.
The Beta Pictoris system holds a special place in astronomy's history: in 1984 it became the first star around which a disk of dust and debris was directly photographed, hinting at planet formation, though astronomers could not confirm any planets there at the time.
