hip-100044

Its story

Few stars are as woven into astronomical history as P Cygni, also designated 34 Cygni. On 18 August 1600, Willem Janszoon Blaeu watched it flare into view like a nova at the Swan's neck; it is now recognised as one of the earliest documented luminous blue variables, so distinctive that the spectroscopic feature it shows —combined absorption and emission lines— bears its name: the «P Cygni profile».