Lunar ephemeris and selenographic coordinates of the earth and sun for 1981 and 1982

Ephemeris data are presented in sections for each month for 1981 and 1982 to provide a time history of lunar coordinates and related geometric information. A NASA Manned Spacecraft Center (MSC) modification of the Jet Propulsion Laboratory ephemeris tape was used to calculate and plot coordinates of the earth, moon, and sun. The ephemeris is referenced to the mean vernal equinox at the nearest beginning of a Besselian year. Therefore, the reference equinox changes from one year to the next between June 30 and July 1. The apparent discontinuity in the data is not noticeable in the graphical presentation, but can be observed in the digital output. The mean equator of epoch is used in all cases. For 1966 to 1970, the same type of data presentation has been prepared in informal MSC documents. The data for 1971 to 1980 and 1983 and 1984 are presented. The computer program used to compute and plot the ephemeris data is described.