optical double star


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Related to optical double star: Binary star system

optical double star

n
(Astronomy) two stars that appear close together when viewed through a telescope but are not physically associated and are often separated by a great distance. Compare binary star
References in periodicals archive ?
Double star director Dave Blane indicate that Alpha Capricorni is an optical double star with components alpha1 Cap and alpha2 Cap having magnitudes 4.
Crossing constellation boundaries eastward takes us to the tail of Aquila, the Eagle, where we find the pretty optical double star 15 Aquilae.