An Etymological Dictionary of Astronomy and Astrophysics
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فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 2 Search : diurnal aberration
constant of diurnal aberration
  پایا‌ی ِ بیراهش روزانه   
pâyâ-ye birâheš ruzâné

Fr.: constante d'aberration diurne   

The quantity 0".3200 ρ cos φ', where ρ is the geocentric distance of the observer measured in units of → equatorial radius the Earth and φ' is the observer's → geocentric latitude. The numerical part is equal to 2πa csc1" / (cP), where a is the equatorial radius of the Earth, P is its → sidereal period of rotation, and c is the → speed of light in vacuum.

constant; → diurnal; → aberration.

diurnal aberration
  بیراهش ِ روزانه   
birâheš-e ruzâné

Fr.: aberration diurne   

The aberration of a star's position due to the rotation of the Earth. Its value depends on the latitude of the observer, and is only 0''.32 in the case of an observer at the equator, where the rotational velocity is greatest.

diurnal; → aberration.