right ascension

Noun

right ascension (plural right ascensions)

1. The angular distance east of the vernal point (“the solar zenith at the March equinox”); the celestial equivalent of longitude.
   • The sun's right ascension in time is useful to the practical astronomer in regular observatories, who adjusts his clock by sidereal time.1809, William Nicholson, “ASCENSION”, in The British Encyclopedia, or Dictionary of Arts and Sciences; […], volume I (A … B), London: Printed by C[harles] Whittingham, […]; for Longman, Hurst, Rees...
   • The right ascensions and declinations obtained by the preceding calculations, are the mean values, to which must be applied the corrections for the Nutation and Aberration Tables XLII. XLIII. in cases where great accuracy is required, as is now done in the Nautical Almanac for 24 of the brightest...1826, Nathaniel Bowditch, Jonathan Ingersoll Bowditch, American Practical Navigator, US Hydrographic Office, page 280

   Synonyms:

   α