in astronomy, is either right or oblique. Right ascension of the sun, or a star, is that degree of the equinoctial, counted from the beginning of aries, which rises with the sun or star in a right sphere. Oblique ascension is an arch of the equator intercepted between the first point of aries, and that point of the equator which rises together with a star in an oblique sphere.

ASCENSION-day, a festival of the Christian church, held ten days before Whitsuntide, in memory of our Saviour's ascension into heaven after his resurrection.

ASCENSION-island, an uninhabited island, lying almost in the midway between Africa and Brazil, in 17° W. long., and 7° S. lat.

ASCENSIONAL difference, the difference between the right and oblique ascension of the same point to the surface of the sphere. See Astronomy.

ASCENT of bodies on inclined planes. See Mechanics.

ASCENT of fluids. See Hydrostatics.