# Angular diameter

the angle that the apparent diameter of a celestial object subtends at the eye of the observer.

Historical *Examples*

Its angular diameter at mean distance is 31′ 5″, or, say, just over ½°.

The Story of the Solar System George F. Chambers

The constant, 220, is the reciprocal of the quotient of the angular diameter of the moon divided by 2.

A Quantitative Study of the Nocturnal Migration of Birds. George H. Lowery.

It appeared about fifteen degrees in angular diameter, showing that we had travelled some thirty thousand miles from it.

To Mars via The Moon Mark Wicks

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