James Webb telescope spots wind blowing faster than a bullet on '2-faced planet' with eternal night

By Ben Turner published 10 hours ago

New James Webb Space Telescope observations of the exoplanet WASP-43b reveal that the hot gas giant is tidally locked, meaning one side permanently faces its sun while the other always stares out into space.



An artist's concept of WASP-43b. (Image credit: NASA, ESA, CSA, Ralf Crawford (STScI))

Scientists using the James Webb Space Telescope (JWST) have mapped the weather on a planet 280 light-years from Earth — a hot gas giant with one side permanently facing its sun and the other cloaked in eternal night.

The Janus-faced planet, named WASP-43b, is composed primarily of hydrogen and helium and is significantly hotter than any gas giant in our solar system, due to its closeness to its host star, which it orbits once every 19 Earth hours. This extreme proximity means WASP-43b is also tidally locked to its star.

Now, researchers have discovered that this tidal lock permanently heats one side of the planet to temperatures around 2,300 degrees Fahrenheit (1,260 degrees Celsius) — hot enough to melt iron. This scorching heat vaporizes rock and carries it into clouds.

The temperature difference between the day and night side, which is comparatively cooler at 1,110 F (600 C), drives fierce winds that can reach speeds of up to 5,600 mph (9,000 km/h), the scientists found. The researchers published their extraterrestrial weather report April 30 in the journal Nature Astronomy.

More:
https://www.livescience.com/space/exoplanets/james-webb-telescope-spots-wind-blowing-faster-than-a-bullet-on-2-faced-planet-with-eternal-night