Eta Carinae: An Evolving View of the Central Binary, Its Interacting Winds and Its Foreground Ejecta

Abstract FUV spectra of ? Car, recorded across two decades with HST/STIS, document multiple changes in resonant lines caused by dissipating extinction our line sight. The flux has increased nearly tenfold, which led to ionization the shells within Homunculus and photodestruction H 2 . Comparison observed profiles CMFGEN model allows separation wind–wind collision shell absorptions from primary wind P Cygni profiles. occulter preferentially obscured central binary interacting winds relative very extended wind. We are now able monitor colliding orbital phase. High-velocity transient occurred most recent periastron passage, indicating acceleration secondary wind, leads a downstream, high-velocity bow shock that is newly generated every period. There no evidence properties winds.