Exoplanet HD 189733b – a planet 63 light-years away from our Solar System residing in the constellation of Vulpecula (the little fox) – has been found to have incredibly powerful supersonic winds that tear up the planet’s surface. Using high resolution spectroscopy, a team from the University of Warwick measured top wind speeds at over 5,400 miles-per-hour.
According to NASA, the planet is approximately ten percent larger than Jupiter, but orbits its parent star at a distance 180 percent closer than Jupiter does to the Sun. The planet’s surface reaches over 3,200 degrees Fahrenheit.
“This is the first ever weather map from outside of our solar system,” said lead researcher Tom Louden. “While we have previously known of wind on exoplanets, we have never before been able to directly measure and map a weather system.”
An exoplanet (also called an extrasolar planet) is any planet that is found to orbit a star other than our Sun. Since the late 1980s, close to 200 exoplanets have been discovered.
Adds AstronomyNow.com: “The University of Warwick discovery is the first time that a weather system on a planet outside of Earth’s solar system has been directly measured and mapped. The wind speed recorded is 20x greater than the fastest ever known on Earth, where it would be seven times the speed of sound.”
As planet HD 189733b crosses its parent star, researchers were able to study changing background illuminations and to measure the related Doppler shift. By measuring sodium absorption spectrums, the team detected a strong eastward wind flow that constantly moves from the heated day side of the planet to the cooler, night side. HD 189733b is tidally locked to its parent star; the planet has a permanent day and night side.
Louden explains: “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.”
Co-researcher Dr. Peter Wheatley of the University of Warwick’s Astrophysics Group said the first-time mapping of the winds will allow scientists and astronomers to study other, more Earth-like exoplanets.
“We are tremendously excited to have found a way to map weather systems on distant planets,” he said. “As we develop the technique further we will be able to study wind flows in increasing detail and make weather maps of smaller planets. Ultimately this technique will allow us to image the weather systems on Earth-like planets.”