galactic disk The flattened component of a spiral galaxy in which, together with many ordinary stars such as the Sun (see disk star), lie the biggest and brightest of stars – the O stars and B stars. The disk is also home to large tracts of interstellar material from which new stars are continually being made. Related category GALAXIES Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |