Atmospheric wind speed measured on exoplanet

Ars Technica: For the first time, scientists have been able to determine wind velocities on an exoplanet. Located some 60 light-years from Earth, HD 189733b is so remote that its winds cannot be measured directly. However, Tom Louden and Peter Wheatley of the University of Warwick in the UK found that by monitoring the exoplanet as it passed in front of its host star they could study the movements of the atoms and molecules in its atmosphere because of the wavelengths of light that they absorbed. The researchers could then determine the particles’ velocities by the amount of redshifting or blueshifting of that light. Once they'd accounted for the planet’s own rotation, the researchers determined that the planet’s winds are moving quickly, at some 8500 km/hour.

Via Physics Today