optical double star


noun

See under double star.

Definition for optical double star (2 of 2)

double star

noun Astronomy.

two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star), or those that are relatively close together and comprise a single physical system (physical double star).
Compare binary star.

Origin of double star

First recorded in 1775–85

British Dictionary definitions for optical double star (1 of 2)

double star

noun

two stars, appearing close together when viewed through a telescope; either physically associated (binary star) or not associated (optical double star) See also binary star, optical double star

British Dictionary definitions for optical double star (2 of 2)

optical double star

noun

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

Scientific definitions for optical double star

double star

See binary star.