SOME EPHEMERIS QUANTITIES AVAILABLE VIA THE NASA/JPL HORIZONS API DO NOT APPLY HERE AND WERE OMITTED. These excerpts are quantities taken from the on-line interface listing at the following URL See: [Table Settings] for the complete quantities listing. https://ssd.jpl.nasa.gov/horizons/app.html Below is a trimmed listing with most of the quantities we would likely use in general purpose ephemerides. Some quantities may still be available even if they are not listed in this truncated table. If an unknown quantity is requested, an error message will be returned. ############################################################################## QUANTITY VALUE(s) ======== =================================================================== 1 Astrometric RA & DEC (Right Ascension and Declination). Can use either the ICRF or B1950/FK4 frame. Adjusted for obserever loca- tion and down-lag light-time. Coordinates are airless. Refraction setting is ignored when using these astrometric coordinates. These coordinates can be local or geocentric. * 2 Apparent RA & DEC (Right Ascension and Declination). These coordinates are the actual apparent geocentric or topocentric coordinates for an observer at the given specified local geographic (GPS) coordinates. ICRF frame only. Optional refraction may also be applied to topocentric coordinates. * 4 Apparent AZ & EL (Azimuth or direction and horizon elevation). These values tell us the compass direction in which to look for an object and its elevation relative to the local horizon. These angles may apply optional refraction. Azimuth refers to the Earth polar axial direction, not the magnetic compass direction, which may deviate from true polar axial north by several degrees. Optional refraction may be applied. A negative value means that the target object is below the local horizon and invisible and a positive value means it is above the local horizon and may be visible depending on local sky and visibility conditions. 7 Local apparent sidereal time. 9 Visual magnitude & surface brightness per square arc second. 10 Illuminated fraction of disc. 11 Defect of illumination. 13 Angular diameter. 14 Observer sub-longitude & sub-latitude 15 Sun sub-longitude & sub-latitude. 16 Sub-Sun position angle & distance. 18 Heliocentric ecliptical longitude & latitude. 19 Heliocentric range & range-rate (distance and radial velocity). 20 Observer range & range-rate (distance and radial velocity). 21 One-way (down-leg) light-time. 23 Sun-Observer-Target ELONGATION angle. 24 Sun-Target-Observer ~PHASE angle. 29 Constellation ID (IAU) - Where to look for Target. 30 (TDB - UT) or Delta T. * 31 Observer ecliptic longitude & latitude. Optional refraction may be applied. 34 Local apparent SOLAR time. 42 Local apparent hour angle of target. --------- NOTE: * Affected by optional atmospheric refraction setting. ########################################################################