Beta 1-2 Cygni – Albireo

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Beta Cygni, known as Albireo, is a celebrated stellar system located in the constellation Cygnus, about 430 light-years from Earth. The primary component, β1 Cygni, is a luminous giant of spectral type K3II with a striking golden hue and a very close companion. The secondary component, β2 Cygni, is a blue main-sequence star classified as B8Ve that shows rapid stellar rotation. It stands out for displaying one of the most remarkable color and effective temperature contrasts in the visible sky. Although the pair has an angular separation of about 35 arcseconds, modern astrometric measurements question whether they form a gravitationally bound system or an optical double.