Shell star variables. Pleione and Gamma Cassiopeiae itself are both variable stars that have intermittent shell episodes where strong shell features appear in the spectrum and the brightness increases or decreases significantly. At other times the shell is not detectable in the spectrum, and even the emission lines may disappear. Shell star A shell star is a star having a spectrum that shows extremely broad absorption lines, plus some very narrow absorption lines. They typically also show some emission lines, usually from the Balmer series but occasionally of other lines. The broad absorption lines are due to rapid rotation of the photosphere,
A Star Is Born (Jay-Z song) were ultimately used in the final mix. Williams himself was not aware of the prominence of his vocals on "A Star Is Born" until his friend Omar Edwards approached him and complimented his performance on the song. "A Star Is Born" received mixed reviews from music critics. Charles Aaron of "Spin" praised its "anthemic, edgy soul-clap" beat and the two rappers' individual performances, lauding Jay-Z in particular as "effortlessly dazzling". "Pitchfork"s Ian Cohen, however, dismissed the song as a "numbingly non-committal salutation" Alexis Petridis, writing for "The Guardian", negatively described "A Star Is Born" as a "mass of indistinct tracks".