Record-breaking supersonic winds discovered on the ultra-hot giant planet KELT-9 b

Star system: KELT-9 | Distance from the Sun: 676 light years

Astronomers using the Keck Planet Finder have detected the most extreme atmospheric winds ever recorded on a gas giant outside our solar system. By observing the ultra-hot Jupiter KELT-9 b as it orbits its star, researchers measured supersonic winds reaching speeds of nearly 12 kilometers per second—over 40,000 kilometers per hour. 

These massive winds carry heat from the permanent dayside to the nightside, revealing a complex global climate. The study also identified a cocktail of vaporized metals in the planet's atmosphere, including iron, titanium, and magnesium, providing a new benchmark for how heat and matter move in the most extreme planetary environments known to science.

Scientific study

Extreme winds on the emerging dayside of an ultrahot Jupiter (external link)