Definition of optical double in English:
A group of two stars which appear to constitute a double star due to their being in the same line of sight as seen from the earth, but are actually at different distances.
- At first he figured that such pairs consisted of two stars vastly distant from each other but coincidentally lying along a single line of sight - a visual phenomenon we now call optical doubles.
- The physical doubles (or binary stars) are much more numerous than the optical doubles.
Definition of optical double in:
- US English dictionary
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