Angular Diameter

The angular diameter or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view.

The angular diameter varies with the arctangent of the ratio between the diameter of an object and its distance from the viewpoint.

Formula

QuantityVariable["δ", "Angle"] == 2*ArcTan[QuantityVariable["d", "Diameter"]/(2*QuantityVariable["D", "Distance"])]

Get the resource:

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Get the formula:

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Use some values:

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$FormulaData[ ResourceObject[ "Angular Diameter"], {QuantityVariable["\[Delta]","Angle"] -> Quantity[0.0460194`, "AngularDegrees"]}]$

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