English

A CORER equipped with a piston inside the core tube that is connected to the lowering cable. When the CORER penetrates the ocean bottom the stopped cable and piston, in effect, provides a suction which overcomes the frictional forces acting between the SEDIMENT and the interior wall of the coring tube.

Composite CENTRIFUGAL FORCE, due to the ROTATION of the EARTH, which acts on moving particles, whose motion is considered relative to that of the EARTH.

PHOTOMETEOR formed by one or more sequences (seldom more than three) of coloured rings of relatively small radius, centred on the SUN or MOON.

A quantity which is applied to an OBSERVATION or function thereof, to diminish or eliminate the effects of ERRORS and obtain an improved value of the OBSERVATION or function. It is also applied to reduce an OBSERVATION to some arbitrary STANDARD. The correction corresponding to a given ERROR is of the same magnitude but of opposite sign. See CHRONOMETER CORRECTION, DIP CORRECTION, INDEX CORRECTION, INSTRUMENTAL CORRECTION, LEAD LINE CORRECTION, PARALLAX CORRECTION, PERSONAL CORRECTION, POLARIS CORRECTION, REFRACTION CORRECTION, SEMIDIAMETER CORRECTION, SEXTANT ALTITUDE CORRECTION, SKY WAVE CORRECTION, ORTHOMETRIC CORRECTION, TIDAL DIFFERENCE.

The CORRECTION of the observed DEPTHS for any departure from true DEPTH due to the method of SOUNDING or to a fault in the measuring apparatus. See also REDUCTION OF SOUNDINGS.

In STEREOSCOPY, the condition that exists when corresponding IMAGES on a pair of PHOTOGRAPHS lie in the same EPIPOLAR PLANE; the absence of Y-PARALLAX.

Very fine particles of solid matter in any part of the universe, including METEORIC DUST and zodiacal light particles in the SOLAR SYSTEM, interstellar matter of uncertain origin in the Milky Way Galaxy, and accumulation of dark matter in other galaxies.