Exoplanet WASP-127b Unleashes Record-Breaking Equatorial Jet Winds

Astronomers using ESO's VLT CRIRES+ measured an exceptionally fast equatorial jet on the bloated hot Jupiter WASP-127b (about 520 light-years away). Doppler shifts in water vapor and carbon monoxide during transit reveal two opposing velocity peaks, indicating a strong eastward jet. After subtracting the planet’s rotation, the jet speed is 7.7 ± 0.2 km/s (roughly 27,700 km/h); including rotation, the maximum equatorial motion reaches about 9 km/s (≈33,000 km/h)—the fastest wind observed on any planet. The result demonstrates a method to map atmospheric circulation on unresolved exoplanets and confirms molecules in the atmosphere, while suggesting cooler poles or high-altitude clouds and paving the way for finer measurements with the Extremely Large Telescope.