Astronomers have discovered recurring radio bursts originating from an exoplanet for the first time ever, marking a breakthrough that would lead us to understand more about the magnetic environment of another planet outside our Solar System.
Beta Pictoris b, which revolves around the relatively young star Beta Pictoris, is 63 light-years away from our planet. It was found by scientists using the MeerKAT radio telescope array based in South Africa in two separate observing periods conducted in 2025 and 2026.
These bursts were detected in the frequency band between 0.85 GHz and 3.5 GHz and exhibited signatures related to radio emissions from aurorae.
However, the discovery by the researchers cannot prove the existence of any other civilisation sending radio signals into space. According to the researchers, the explanation of the fact might be the strong auroras created by the interaction of the charged particles and the planet’s magnetosphere.
This fact is crucial as usually, the radio emissions detected from the stellar systems with exoplanets come from the star rather than the exoplanet itself.
Still, in this particular case, as the scientists say, they succeeded in determining the source of the signals accurately. Thus, the research can provide scientists with an opportunity to gather direct information regarding the magnetic field of the exoplanet.
A radio signal with an unusual signature
Repetitive radio bursts characterised by very high circular polarisation emanated from the Beta Pictoris system, containing a young planetary system located 63 light-years away from Earth.
The burst is comparable to the radio bursts that emanate from Earth and other planets such as Jupiter.
It is believed that the radio burst occurs as a result of the Electron Cyclotron Maser Instability (ECMI) process, in which charged particles interact with the magnetic field, causing radio emission. Given the strong relationship between ECMI and the magnetic field, it offers clues regarding the strong magnetic field surrounding Beta Pictoris b.
The difficulty in analysing this phenomenon lies in the problem of detecting whether the radio emission comes from the planet or the much bigger and hotter host star.
This was made possible through the use of distant quasars as guides and mapping of the radio emission.
The researchers are now able to establish that the radio emission originates from Beta Pictoris b and not the star. This is significant in that the researchers can be able to detect the radio emission from the exoplanet.
The invisible magnetic field leaves a visible clue
The radio bursts tell astronomers more than simply where the emission originated.
According to the researchers, the characteristics of the signal are consistent with an auroral process controlled by a strong planetary magnetic field. Their calculations indicate that Beta Pictoris b has a magnetic field far more powerful than Earth's.
The planet is already an unusual object. It is a young gas giant estimated to have roughly ten times Jupiter's mass and was first discovered in 2008.
It also rotates extremely quickly. Beta Pictoris b completes a rotation in roughly 8 to 9 hours, a rate that could help drive its magnetic activity.
A planet's magnetic field is generated by processes inside its interior, commonly described as a dynamo. Exactly how these dynamos operate in massive young planets is still an active area of research.
Previous models had predicted that Beta Pictoris b could possess a strong magnetic field. The radio observations now provide an independent way to test those predictions.
The researchers describe the measurement as the first direct determination of an exoplanet's magnetic-field strength.
That is potentially more important than the radio signal itself. Magnetic fields influence how planets interact with their surrounding space environment and can affect the behaviour of charged particles around them.
Why astronomers care about planetary magnetic fields
Magnetic fields on distant exoplanets are hard to detect since they cannot be photographed easily.
Thus, astronomers rely on indirect evidence to detect their presence through auroral radio emission, since the frequency and behavior of the radiation depend on magnetic fields' strengths.
Beta Pictoris b thus serves as a great example of the application of the technique on other planets as well.
The scientists found another seven gas giants in five planetary systems near Earth that could be researched through similar methods.
But current radio telescopes have limitations regarding sensitivity. The team estimates that the next generation of observatories will increase sensitivity by about five to seven times, allowing researchers to study further away planetary radio emissions.
This would allow researchers to examine more planets for their magnetic environment.
Moreover, it could help scientists learn more about the evolution of giant planets. In fact, Beta Pictoris b is a young, huge and fast-rotating planet, which is quite useful in examining the connection between planetary interior, rotation and magnetosphere.
This is not a signal from aliens. However, it shows how planets located many light-years away from us provide information about their surroundings.
What the radio bursts tell us about this distant world
The existence of Beta Pictoris b as a very large and young planet revolving around a nearby star had already been established, and now a novel trait has been added - a very powerful magnetic field.
Further questions could now be addressed by the scientists.
Is the field stable, and does its power vary with time? How much does the radiation depend on the planet's rapid spin? Do the other large planets emit comparable radio signals?
These questions can be answered only after further observation.
The discovery made by the researchers has yet to be published in a refereed journal and is presently only a preprint on arXiv. That means that the results should be peer-reviewed scientifically.
However, this observation opens up a new method of studying exoplanets. Not only could the effect of a planet upon the surrounding star or light travelling through the atmosphere of the planet be used to gather information about the world, but also the planet's own radio emission could serve for this purpose.
This is an impressive amount of information one could get about a planet which is located 63 light-years away.
FAQ
1. Beta Pictoris b: what is it?It is a relatively young giant gas planet which orbits Beta Pictoris – a star located at a distance of about 63 light-years from Earth. The planet was discovered in 2008; the mass of the planet is estimated to be 10 times more massive than the mass of Jupiter.
2. Is there any indication of the presence of life on Beta Pictoris b because of the presence of radio waves?
No. According to scientific research, the bursts seem to appear due to a natural phenomenon – auroras and the interaction of charged particles and the magnetic field of the planet.
3. What is the meaning of the radio waves discovery?
The origin of radio waves can be attributed to the Electron Cyclotron Maser Instability – a magnetic phenomenon. If that is the case, the signal will help to measure the magnetic field of the planet.
4. What is the strength of the magnetic field of the Beta Pictoris b?
According to the information provided by scientists, the strength of the magnetic field of the planet is thousands of times stronger than the magnetic field of the Earth.
