declination axisThe axis at right angles to the polar axis about which a telescope on an equatorial mounting is turned in order to make adjustments in declination. The optical axis then follows a particular hour circle across the sky.
one of the axes of an equatorial mount of a telescope. The declination axis is perpendicular to the polar axis. The telescope is rotated about the declination axis as it is directed to a given point on the celestial sphere.
declination axis[‚dek·lə′nā·shən ‚ak·səs]
For an equatorial mounting of a telescope, an axis of rotation that is perpendicular to the polar axis and allows the telescope to be pointed at objects of different declinations.