An orbit that is defined in a highly precise manner with due regard taken for accurate constants and observational data, and precision computational techniques including perturbations. 
An orbit that is defined in a highly precise manner with due regard taken for accurate constants and observational data, and precision computational techniques including perturbations. 
Related Terms 
FEASIBILITY ORBITAn orbit that can be rapidly and inexpensively computed on the basis of simplifying assumptions (e.g., twobody motion, circular orbit, rectilinear orbit, threebody motion approximated by two twobody orbits, etc.) and yields an indication of the general feasibility of a system based upon the orbit without having to carry out a fullblown definitive orbit computation. 
AIR ALMANAC

ANTINODEEither of the two points on an orbit where a line in the orbit plane, perpendicular to the line of nodes, and passing through the focus, intersects the orbit. 
APHELIONThat point in the elliptical orbit of a body about the sun farthest from the sun. That point nearest the sun is called PERIHELION. 
APOCENTERIn an elliptical orbit, the point in the orbit which is the farthest distance from the focus, where the attracting mass is located. The apocenter is at one end of the major axis of the orbital ellipse. The opposite is PERICENTER, PERIFOCUS, PERIAPSIS. Also called APOAPSIS, APOFOCUS 
APOGEEThat orbital point of a noncircular orbit farthest from the center of attraction. Opposite is PERIGEE 
ALMANACA periodical publication of ephemeral astronomical data. If information is given in a form and to a precision suitable for marine navigation, it is called a nautical almanac. See also nautical almanac; if designed primarily for air navigation, it is called an air almanac. See also EPHEMERIS, ASTRONOMICAL ALMANAC. 
APASTRONThe point of the orbit of one member of a double star system at which the stars are farthest apart. That point at which they are nearest together is called PERIASTRON. 
APSISEither of the two orbital points nearest or farthest from the center of attraction, the perihelion and aphelion in the case of an orbit about the sun, and the perigee and apogee in the case of an orbit about the earth. The line connecting these two points is called LINE OF APSIDES. 
ABERRATION

MarineProHelp 2018  2020