Definition

The angle between a celestial body and the horizon, as measured by an astrolabe, cross-staff, back-staff, quadrant or sextant at sea. The sun's angle of declination at noontime, for example, needed in the calculation of a ship's latitude.

Observer's latitude = 90 degrees - observed angle +(in winter) or - (if summer) the sun's recorded declination for that date.

Related Images

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Officers trying to determine, with the use of a sextant, the sun's angle of declination at noontime

Officers trying to determine, with the use of a sextant, the sun's angle of declination at noontime
Image ID: 1190
Record ID: 113