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Health & Science3h 50m ago

Astronomers detected that the evening terminator of exoplanet WASP-121 b is hotter than its morning one, using the James Webb Space Telescope to observe the planet's silhouette shape change during a single transit.

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WASP-121 b (exoplanet)

Who
Astronomers, James Webb Space Telescope, Cyril Gapp
What
Astronomers detected that the evening terminator of exoplanet WASP-121 b is hotter than its morning one, using the James Webb Space Telescope to observe the planet's silhouette shape change during a single transit.
When
Tue, 16 Jun 2026 08:08:23 GMT · 3h 50m ago
Where
WASP-121 b (exoplanet) ·
Why
The evening side runs hotter due to a strong equatorial jet that drags heat eastward from the planet's permanently lit dayside.
The Frontline Impact

How this affects you

This discovery marks the first time a planet's rotation has been measured during a single transit to deduce its weather, providing a new method for astronomers to study atmospheric dynamics and climate on distant exoplanets like ultrahot Jupiters.

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2 events in this thread
  1. Health & Science3h 50m ago
    Astronomers detected that the evening terminator of the ultrahot Jupiter WASP-121 b is hotter than its morning one.
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  2. Currently Reading3h 50m ago
    Astronomers detected that the evening terminator of exoplanet WASP-121 b is hotter than its morning one, using the James Webb Space Telescope to observe the planet's silhouette shape change during a single transit.

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