An Etymological Dictionary of Astronomy and Astrophysics

English-French-Persian

فرهنگ ریشه‌شناختی اخترشناسی-اخترفیزیک

Homepage  Preliminaries  Abbreviations  Acknowledgments  References 
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Coordinated Universal Time (UTC)
  زمان ِ جهانی ِ هم‌آراسته  
zamân-e jahâni-ye hamrârâsté
Fr.: temps universel coordonné  

An international high-precision time standard based on the Greenwich Mean Time and adjusted to compensate for divergence from atomic time. It is based on the non-uniform rotation of the Earth (UT1) and the perfectly uniform international atomic time (TAI). UTC differs from TAI by the total number of → leap seconds, so that UT1-UTC stays smaller than 0.9 sec in absolute value.

See also: → coordinate; → universal; → time.