aberration, constant of


aberration, constant of

      in astronomy, the maximum amount of the apparent yearly aberrational displacement of a star or other celestial body, resulting from the Earth's orbital motion around the Sun. The value of the constant, about 20.49″ of arc, depends on the ratio of Earth's orbital velocity to the velocity of light. James Bradley (Bradley, James), the British astronomer who in 1728 discovered the aberration of starlight, estimated the value of the constant at about 20″ and from this calculated the velocity of light at 295,000 kilometres (183,300 miles) per second, within a few thousand kilometres per second of the presently accepted value. The aberrational ellipse described by the image of a star in the course of a year has a major axis equal in angular distance to twice the constant of aberration.

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  • aberration constant — aberacijos kampas statusas T sritis fizika atitikmenys: angl. aberration angle; aberration constant; angle of aberration vok. Aberrationskonstante, f; Aberrationswinkel, m rus. постоянная аберрации, f; угол аберрации, m pranc. angle de… …   Fizikos terminų žodynas

  • Constant of aberration — Constant Con stant, n. 1. That which is not subject to change; that which is invariable. [1913 Webster] 2. (Math.) A quantity that does not change its value; used in countradistinction to {variable}. [1913 Webster] 3. (Astron.) A number whose… …   The Collaborative International Dictionary of English

  • Constant — Con stant, n. 1. That which is not subject to change; that which is invariable. [1913 Webster] 2. (Math.) A quantity that does not change its value; used in countradistinction to {variable}. [1913 Webster] 3. (Astron.) A number whose value, when… …   The Collaborative International Dictionary of English

  • Constant of integration — Constant Con stant, n. 1. That which is not subject to change; that which is invariable. [1913 Webster] 2. (Math.) A quantity that does not change its value; used in countradistinction to {variable}. [1913 Webster] 3. (Astron.) A number whose… …   The Collaborative International Dictionary of English

  • aberration angle — aberacijos kampas statusas T sritis fizika atitikmenys: angl. aberration angle; aberration constant; angle of aberration vok. Aberrationskonstante, f; Aberrationswinkel, m rus. постоянная аберрации, f; угол аберрации, m pranc. angle de… …   Fizikos terminų žodynas

  • Aberration De La Lumière — L aberration de la lumière a été découverte par l astronome James Bradley en 1725, mais seulement publiée en 1727. Elle se traduit par le fait que la direction apparente d une source lumineuse dépend de la vitesse de celui qui l observe, de la… …   Wikipédia en Français

  • Aberration de la lumiere — Aberration de la lumière L aberration de la lumière a été découverte par l astronome James Bradley en 1725, mais seulement publiée en 1727. Elle se traduit par le fait que la direction apparente d une source lumineuse dépend de la vitesse de… …   Wikipédia en Français

  • Aberration of light — Light from location 1 will appear to be coming from location 2 for a moving telescope due to the finite speed of light, a phenomenon known as the aberration of light. The aberration of light (also referred to as astronomical aberration or stellar …   Wikipedia

  • Aberration de la lumière — Le phénomène de l aberration de la lumière a été découvert par l astronome James Bradley en 1725, mais seulement publié en 1727. Il se traduit par le fait que la direction apparente d une source lumineuse dépend de la vitesse de celui qui l… …   Wikipédia en Français