Astrophysics (index)about

Optical Double

(two stars that look like one with naked eye)

An Optical Double is a pair of stars that look like one when viewed without a telescope, but have been distinguished through use of telescopes, perhaps with additional instruments.

It can simply be two stars in the same line of vision though distant from each other. Often the term is intended to exclude an actual Binary Star (co-orbiting stars).

(star type)

Referenced by:
Blended Spectra