Amazing wind speeds have been measured on the Sun by the SUMER instrument on SOHO
Below: Shifts in the wavelengths of ultraviolet light from highly ionized neon atoms (Ne VIII), seen by SUMER, revealed wind speeds of up to 320 000 kilometres per hour. Two scans were performed on this region - one from east to west, the second from west to east.
This image is extracted from the paper by Winebarger and colleagues, published in Astrophysical Journal Letters, Volume 567, pp. L89-L92