A windy day on HD 189733b is nothing to take lightly.
The planet, located about 63 light years away in the constellation Vulpecula, has winds reaching 5,400 mph, roughly 20 times faster than anything ever experienced on Earth.
Granted, everything about HD 189733b is extreme. It's about 10 percent bigger than Jupiter, but its located 180 times closer to its parent star than Jupiter is to the sun, far closer than even Mercury, the innermost planet in the solar system.
"As parts of HD 189733b's atmosphere move towards or away from the Earth the Doppler effect changes the wavelength of this feature, which allows the velocity to be measured," lead researcher Tom Louden said in a statement. "This is the first ever weather map from outside of our solar system."
Astronomers used HARPS, the High Accuracy Radial velocity Planet Searcher, in La Silla, Chile, to watch the planet as it passed in front of its host star, relative to the telescope's line of sight.
"The surface of the star is brighter at the center than it is at the edge, so as the planet moves in front of the star the relative amount of light blocked by different parts of the atmosphere changes. For the first time we've used this information to measure the velocities on opposite sides of the planet independently, which gives us our velocity map," Louden said.
