Updated
Updated · spacedaily.com · Aug 24
Astronomers Measure 33,000 km/h Jet on WASP-127b, Probing Weather 520 Light-Years Away
Updated
Updated · spacedaily.com · Aug 24

Astronomers Measure 33,000 km/h Jet on WASP-127b, Probing Weather 520 Light-Years Away

2 articles · Updated · spacedaily.com · Aug 24

Summary

  • WASP-127b’s equatorial atmosphere was measured at up to 33,000 km/h, with a more direct Doppler split indicating a 7.7 km-per-second jet and model-based retrievals pushing the flow near 9 km/s.
  • CRIRES+ on ESO’s Very Large Telescope captured one transit and found water-vapor and carbon-monoxide signals split into two peaks—one approaching, one receding—interpreted as opposite limbs of an eastward superrotating jet.
  • The puffy gas giant, 1.31 times Jupiter’s radius but only 0.165 Jupiter masses, is unusually favorable for transit spectroscopy because its broad, low-density atmosphere imprints stronger molecular fingerprints on starlight.
  • The result matters less as a wind-speed record—it was surpassed within four weeks by WASP-121b—than as a demonstration that Doppler spectroscopy can separate equator, limbs and possible polar differences on an unresolved exoplanet.

Insights

What terrifying atmospheric forces drive perpetual 33,000 km/h hurricanes on a bloated exoplanet where water vapour is literally torn apart?
Could unseen magnetic fields be the only thing stopping 33,000 km/h winds from tearing apart the atmospheres of distant gas giants?
How do scientists map the violent, supersonic storms of a world 520 light-years away without ever actually seeing its surface?

Record-Breaking Jet Stream on WASP-127b: How Astronomers Measured 33,000 km/h Winds Across Light-Years

Overview

WASP-127b, a puffy gas giant orbiting extremely close to its star, is tidally locked so that one side always faces the star while the other remains in darkness. This creates a huge temperature difference, driving violent winds across the planet. Because WASP-127b has no solid surface, there is no friction to slow these winds, allowing a supersonic jet stream to form at the equator, reaching speeds of about 33,000 km/h. Astronomers detected this jet stream by observing starlight filtering through the planet’s atmosphere during transit, using Doppler shifts and a double-peak spectral signal to confirm the extreme wind speeds.

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