"Computer programming." . . "Orbits." . . . . "Flight paths." . . "Artificial satellites." . . "The analysis and programming associated with performing a differential correction to orbital elements and/or station positions from weighted observations of range, range rate, azimuth-elevation and/or right ascension-declination on close earth satellites are described. The ephemeris computation considers perturbations due to the earth's gravitational potential as described by a spherical harmonic representation through n = m = 5, the lunar gravitational potential, air drag and radiation pressure. All observations may be simulated in punched card form for the purposes of conducting geometric studies. (Author)."@en . . . "Differential orbit correction and station locator program doc - ii"@en . . . . . . . . . . "WOLF RESEARCH AND DEVELOPMENT CORP WEST CONCORD MASS." . . "Differential equations." . . "Programming languages." . .