Large turbulent elements in supergiant photospheres

During the cool phase of the super-supergiant HR 8752, which happened around 1973, when the star's spectral type was K2...K5 Ia⁺, the most probable vertical extent of the main turbulent elements in the star's photosphere was about 6 times the density scale height, which is about half the stellar radius. In early-type photospheres (class Ia) it is about 10 times the atmospheric density scale height (about 0.25 of the stellar radius), while in less extreme (luminosity class Ib) medium-type supergiants the most probable vertical extent of the elements is approx. 8 times the density scale height (0.05R). Large turbulent elements are apparently a common feature in supergiant photospheres; the more extreme the supergiant the larger the relative size of the eddies.