An Etymological Dictionary of Astronomy and Astrophysics

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فرهنگ ریشه‌شناختی اخترشناسی-اخترفیزیک

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Aristarchus' inequality
  ناهموگی ِ اریستارخوس  
nâhamugi-ye Aristarchus
Fr.: inégalité d'Aristarque  

Put in modern notation, if α and β are acute angles and if β <α, then sin α / sin β <α / β < tan α / tan β. Aristarchus probably used this inequality to show that the Sun is between 18 and 20 times as far from the Earth as the Moon is.

See also: Aristarchus of Samos (c.310-c.230 BC); → inequality.