Astronomers have unveiled compelling evidence that magnetic fields significantly influence weather patterns on exoplanets by analyzing the intense winds in the atmospheres of seven superhot Jupiters.
This diagram illustrates the magnetic activity of a superhot Jupiter. Image credit: ESO / M. Kornmesser / L. Calçada.
The Earth’s magnetic field plays a crucial role in atmospheric dynamics and is vital for maintaining conditions suitable for life.
Additionally, magnetic fields are present on other planets in our solar system, such as Jupiter and Saturn.
However, for the past 15 years, measuring the strength of an exoplanet’s magnetic field directly has remained a challenge.
“This breakthrough opens a new frontier in exoplanet science,” said Dr. Julia Seidel, an astronomer at the Lagrangian Laboratory at the Côte d’Azur Observatory.
“For the first time, we can compare the magnetic environments of distant worlds, a crucial step toward understanding which planets can support water and potentially host life as we know it.”
The research team gauged wind speeds on seven tidally locked superhot Jupiters orbiting various stars.
Measured wind speeds ranged from about 7,200 km/h to over 25,000 km/h—much faster than the maximum wind speed of approximately 1,500 km/h recorded on Jupiter.
Using data collected from the ESPRESSO instrument on ESO’s Very Large Telescope and a similar tool on the Gemini North telescope, the scientists uncovered a surprising trend: wind speeds decreased as planetary temperatures increased.
“This observation is counterintuitive, as hotter planets should theoretically have more energy to accelerate winds,” noted Professor Vivienne Parmentier from the Lagrangian Laboratory at the Côte d’Azur Observatory.
“Something must account for the reduced wind speeds on these hotter planets.”
The researchers deduced that the presence of a planet-wide magnetic field is the most plausible explanation. These magnetic fields can act as brakes, moderating the movement of charged particles within the atmosphere.
From their findings, the authors inferred the magnetic field strength of each studied planet, discovering that their intensities were comparable to those found in our solar system—approximately four times stronger than Saturn’s or about half of Jupiter’s strength.
Such formidable magnetic fields influence more than just the winds on these distant worlds.
“On Earth, we experience the beauty of the Northern and Southern Lights. Solar particles interact with magnetic fields, guiding them to the poles where they collide with atmospheric gases, creating a captivating display of colors,” explained Dr. Viviana Prinos from ESO.
“Magnetically driven auroras on these exoplanets could be even more breathtaking.”
This groundbreaking study was published in today’s issue of Nature Astronomy.
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JV Seidel et al. The magnetic field strength of a hot giant exoplanet matches that of our solar system. Nat Astron, published online June 2, 2026. doi: 10.1038/s41550-026-02870-1
Source: www.sci.news
