NODDY, the name applied to a sea-bird, Anous stolidus, one of the Terns (q.v.), from its showing so little fear of man as to be accounted stupid. It is heavier in flight than most terns, with shorter wings and less forked tail. The plumage is of a uniform sooty hue, except the light grey crown of the head. The noddy is very generally distributed throughout tropical and sub-tropical oceans. It breeds in astounding numbers, on low cays and coral-islets, making a nest composed of sea-weed or small twigs. Other birds of the same genus are : the darker Pacific noddy (A. s. sidgwayi), the still darker Galapagos noddy (A. s. galapago ensis) and the white-headed noddy (A. leucocapillus). There is also the white noddy (Gygis alba).
NODE [Lat. nodus, a loop] , in astronomy, one of two oppo site points at which a heavenly body passes through the prin cipal co-ordinate plane to which its motion is referred. In the
case of the heavenly bodies this plane is commonly that of the ecliptic, but, in special cases, the plane through the origin parallel to the earth's equator or the plane of a planet's orbit is used. The ascending node is that at which the body moves from the south or negative towards the north or positive side of the plane. The moon's nodes are the points in which its path intercepts the plane of the ecliptic. In the geometry of curves, a node is the name given to the loop formed by a continuous curve crossing itself, the point of crossing is termed a "double point," and at it there are two non-coincident tangents to the curve ; the remaining species of double points, termed "acnode," "spinode" or "cusp," admits of two coincident tangents (see CURVE).