Eta Carinae
The Eta Carinae star system is currently one of the most massive stars that can be studied in great detail. Until recently Eta Carinae was thought to be the most massive single star, but the system's binary nature was proposed by the Brazilian astronomer Augusto Damineli in 1996 and confirmed in 2005. Both component stars are largely obscured by circumstellar material ejected from Eta Carinae A, and basic properties such as their temperatures and luminosities can only be inferred. Rapid changes to the stellar wind in the 21st century suggest that the star itself may be revealed when dust from the great eruption finally clears.