This folder contains data on the maximum elongations of minor planets between 1950 Apr. 29 and 2060 Dec. 7 The sequence of columns is: Asteroid number; date of maximum elongation in format yyyy/mm/dd; maximum elongation from the Sun in degrees; right ascension in hours and minutes (2000 coordinates) on the date of maximum elongation; declination in degrees (2000 coordinates) on the date of maximum elongation; date of brightest visual magnitude; brightest visual magnitude; date of closest approach to Earth; closest approach to Earth in Astronomical Units. These data were computed by a program written by John Reed which utilizes the JPL DE200 planetary ephemeris, orbital elements by the Minor Planet Center, and employs Cowell's method to compute planetary perturbations by nine planets (except for 134340 Pluto) and the Moon. An integration step of one day was used except where close approaches to Earth or Sun occurred, in which case the integration step was reduced to 0.1 days. Data were computed for 12h UT rather than the usual 0h with the assumption that if at 12h on the indicated date the parmeter was more extreme than at 12h on the previous or following date, then actual extremum in nearly every case occurred between 0h and 23h59m UT on the indicated date. Maximum elongation rather than the more familiar opposition to the Sun is utilized in these tables. This is especially useful as true opposition is often not achieved in many close Earth approaches. These would be missed in a program which searched for oppositions (difference of 12 hours right ascension between the object and the Sun). With a very few exceptions for asteroids with remarkable orbits, data are provided only for elongations at least 60 degrees from the Sun for which brightest magnitude occurs at least 50 degrees from the Sun. These data have been computed for all of the first 30000 numbered asteroids. The data are sorted first by number, second by date, in the files opp00001.txt, opp00201.txt, ..., opp29801.txt for the 200 asteroids beginning with the indicated number for all dates 1950/04/29 through 2060/12/07. Beyond number 30000 and finishing with number 215442 these data have been computed only for asteroids with unusual orbits, or which appear likely to approach the Earth within 0.500 AU or become at least as bright as magnitude 15.0 within the 110 year interval covered in this study. The files 1950opp.txt, 1960opp.txt, ..., 2050opp.txt are in temporal rather than numerical sequence for the decade beginning with the indicated year but only for those events in which visual magnitude 15.0 or brighter, or approaches to the Earth within 0.500 AU, or both, are achieved. All data except the magnitude should be regarded as reliable. Magnitudes in most cases have rotational and aspect variation each of a few tenths, and for many higher numbered asteroids have errors of several tenths in even the average values, with even larger errors in a few cases. For asteroids in the main belt or further distant the dates of maximum elongation, greatest brightness, and minimum distance from Earth all occur within a few days of one another and it is convenient to put data for the three closely associated events on the same line. During close approaches to Earth it is fairly common to have two maximum elongations (rarely, three) associated with a single minimum distance and/or brightest magnitude. These are written on two (rarely, three) consecutive lines. Often it happens for one of the two (rarely, three) maximum elongations occurring within a few months of one another that brightest magnitude and/or closest distance to Earth are far removed in time from maximum elongation. These cases are shown by the symbols / / with omitted dates. The stated magnitude and distance from Earth are then for the date of opposition. It is useful to compute the ephemeris for the entire interval between the two consecutive dates of maximum elongation from the Sun which are associated with a single close approach to Earth to find just how the asteroid is moving through the sky.