Here's a sample template for an e'mail message to request xyz coordinates from Horizons for use with Celestia. You will have to edit the returned message into the format that Celestia uses. The message must be mailed to the address "horizons@ssd.jpl.nasa.gov" The subject must be "JOB" ( do not include the quotes in either ) The body of the message should consist of the following text which is between the lines of =====. Don't include those lines. The lines starting with "!$$" are required, however. Replace the fields ending in "here" with appropriate values. Don't touch any of the other lines until you've read and understood Horizons' documentation. ========================================================== !$$SOF (ssd) JPL/Horizons Execution Control VARLIST EMAIL_ADDR = 'your address here' ! 'you@there.com' COMMAND = 'object name or id# here' ! e.g. 'TRITON' OBJ_DATA = 'NO' MAKE_EPHEM = 'YES' TABLE_TYPE = 'VECTORS' CENTER = '@10' REF_PLANE = 'ECLIPTIC' SITE_COORD = '0,0,0' START_TIME = 'starting date here' ! e.g. '1989-Aug-23 09:00' STOP_TIME = 'ending date here' ! e.g. '1989-Aug-27 09:00' STEP_SIZE = 'sample period here' ! e.g. '10m' or '2d' REF_SYSTEM = 'J2000' OUT_UNITS = 'KM-D' VECT_TABLE = '1' VECT_CORR = 'NONE' TIME_DIGITS = 'MIN' CSV_FORMAT = 'NO' VEC_LABELS = 'NO' ELM_LABELS = 'NO' R_T_S_ONLY = 'NO' CA_TABLE_TYPE= 'EXTENDED' CALIM_SB= '0.1' CALIM_PL= '.1, .1, .1, .1, 1.0, 1.0, 1.0, 1.0, .1, .003' !$$EOF++++++++++++++++++++++++++++++++++++++++++++++++++++++ ==========================================================