Overview
- A peer‑reviewed paper published on June 2, 2026 presents the strongest indirect evidence yet that some exoplanets generate global magnetic fields based on a population study of seven ultra‑hot Jupiters.
- Using high‑resolution spectrographs ESPRESSO on the VLT and MAROON‑X on Gemini North, the team measured Doppler shifts to map wind speeds that ranged from about 7,200 km/h to over 25,000 km/h.
- The surprising pattern was that hotter planets had slower winds, a trend the authors attribute to magnetic fields braking ionised atmospheric flows and redirecting energy.
- From that magnetic braking model the researchers inferred field strengths roughly four times that of Saturn up to about half of Jupiter’s, with implications for planetary interiors, aurorae, and atmospheric loss.
- The result is an indirect, population‑level detection that complements long‑running direct radio searches, and the team plans follow‑up surveys of cooler planets and future observations with next‑generation telescopes to test the boundary where magnetism dominates.