Astronomers have detected the fastest atmospheric jet stream ever recorded, with winds reaching 33 000 km/h (20 505 mph), on the gas giant exoplanet WASP-127b, located over 500 light-years from Earth.
- Tornados, cyclones and hurricanes wreak havoc on Earth, but scientists have now detected planetary winds on an entirely different scale, far outside the Solar System.
Researchers reporting in Astronomy & Astrophysics have discovered powerful winds traveling at speeds of 33 000 km/h (20 505 mph) on the gas giant exoplanet WASP-127b, representing the fastest atmospheric jetstream ever recorded on any planet. The findings, published in Astronomy & Astrophysics, offer valuable insights into the weather patterns and atmospheric dynamics of planets located far beyond our Solar System.
Researchers analyzed the atmosphere of WASP-127b during a transit of its host star using the CRIRES+ instrument on the European Southern Observatory’s Very Large Telescope (ESO’s VLT) in Chile.
Discovered in 2016, this exoplanet is situated over 500 light-years (4.73 × 10¹⁵ km) from Earth. While slightly larger than Jupiter, WASP-127b has only a fraction of Jupiter’s mass, giving it a low density frequently described as “puffy.”
The analysis detected water vapor and carbon monoxide molecules within the atmosphere of WASP-127b. A surprising double-peaked signal revealed that one portion of the atmosphere is moving toward Earth, while another is moving away at comparable high speeds.
Researchers attribute this phenomenon to a supersonic jetstream encircling the planet’s equator, likely caused by steep temperature gradients and rotation dynamics.
WASP-127b’s equatorial jetstream is estimated to move at 32 400 km/h (20 132 mph), nearly six times faster than the planet’s rotation speed. By comparison, the fastest wind measured in the Solar System occurred on Neptune, where winds reached 1 800 km/h (1 118 mph). This discovery highlights the extreme atmospheric conditions that can occur on exoplanets and underscores the unique features of WASP-127b.
Beyond the equatorial jet stream, researchers observed significant temperature variations across latitudes. WASP-127b’s polar regions appear cooler than its equatorial regions.
Additionally, researchers detected slight temperature differences between the morning and evening terminators—the zones transitioning between the day and night sides of the planet. These findings indicate a complex interaction between heat redistribution and atmospheric circulation.
References:
1 CRIRES+ transmission spectroscopy of WASP-127 b – Detection of the resolved signatures of a supersonic equatorial jet and cool poles in a hot planet – Astronomy & Astrophysics – January 21, 2025 – – OPEN ACCESS
2 Extreme supersonic winds measured on planet outside our Solar System – ESO – January 21, 2025
Featured image credit: ESO/L. Calçada