JWST reveals dawn-dusk atmosphere split on ultra-hot exoplanet WASP-121 b
New James Webb Space Telescope observations reveal distinct atmospheric conditions between dawn and dusk on the ultra-hot exoplanet WASP-121 b.
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📍 How it ended
Data from the James Webb Space Telescope identified a dawn-dusk atmospheric split on the ultra-hot exoplanet WASP-121 b, where water vapor behaves differently across the planet's twilight zones. This discovery coincided with the development of new methods for detecting clouds and characterizing the weather patterns of distant alien worlds. The story quieted without a definitive conclusion in the coverage.
Epilogue added 22d ago, after coverage quieted.
The brief
Data captured by the James Webb Space Telescope shows that the atmosphere of WASP-121 b varies significantly between its morning and evening sides. The planet experiences extreme heat, which results in the breakdown of water molecules. ScienceBlog.com, ScienceDaily, and Phys.org report that these differences create distinct weather patterns at dawn and dusk.
Related coverage from IFLScience discusses atmospheric phenomena on WASP-94A b, where rock clouds appear to form and vanish on a diurnal cycle. Universe Today highlights that these findings are supported by a new method for detecting clouds on exoplanets. Future updates will likely depend on continued analysis of JWST imaging and the application of new cloud-detection methodologies.
Coverage does not yet specify the full chemical composition of these dawn-dusk atmospheric divides.
Synthesized by PULSE from the headlines below under a strict no-invention contract. ✓ fact-checked: all claims supported by sources Updated 22d ago.
Quick answers
What is unique about the atmosphere of WASP-121 b?
The planet exhibits an atmospheric split, with weather patterns differing between the dawn and dusk sides.
How does the planet's temperature affect its atmosphere?
The temperatures are high enough to cause water molecules to break apart.
What new method is being used in exoplanet research?
A new cloud-detecting method is being implemented to help astronomers better characterize exoplanet atmospheres.
Coverage (5)
- A Planet So Hot Its Water Falls Apart Has Different Weather at Dawn and Dusk ScienceBlog.com · 46d ago
- New Cloud-Detecting Method Will Help Astronomers Characterize Exoplanets Universe Today · 46d ago
- James Webb reveals two completely different twilights on an alien world ScienceDaily · 46d ago
- WASP-94A b: The Exoplanet Where Clouds Of Rock Form In The Morning And Vanish Every Night IFLScience · 46d ago
- JWST reveals dawn-dusk atmosphere split on ultra-hot exoplanet WASP-121 b Phys.org · 46d ago
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