Objects In This Ephemeris -------------------------------------------------------- This ephemeris contains the ITRF93 coordinates for the following DSN stations. Name Id-code ------------- ------- DSS_12..............399012 DSS_13..............399013 DSS_14..............399014 DSS_15..............399015 DSS_16..............399016 DSS_17..............399017 DSS_23..............399023 DSS_24..............399024 DSS_25..............399025 DSS_26..............399026 DSS_27..............399027 DSS_28..............399028 DSS_33..............399033 DSS_34..............399034 DSS_42..............399042 DSS_43..............399043 DSS_45..............399045 DSS_46..............399046 DSS_53..............399053 DSS_54..............399054 DSS_61..............399061 DSS_63..............399063 DSS_65..............399065 DSS_66..............399066 PARKES..............399005 Approximate Time Coverage From: Jan 1, 1950 To : Jan 1, 2050 Status -------------------------------------------------------- This is the current best estimate for the position of ITRF93 locations of the DSN tracking stations as of 28 May 1997. Currently, no formal updates to this ephemeris are planned. Note however that the locations of the stations are given with respect to the 'EARTH_FIXED' frame. Production/History of this Ephemeris -------------------------------------------------------- This ephemeris was produced by Bill Taber of the Navigation Ancillary Information Facility (NAIF) at the Jet Propulsion Laboratory on 29 Oct 1997 for use by all SPICE customers. It was produced using the SPICE program "pinpoint" version 1.2.0. The actual text inputs to pinpoint are included as an appendix at the end of this note. Usage -------------------------------------------------------- To determine the state of a station with respect to an object other than another station you will need at a minimum a PCK file giving the relationship between the EARTH_FIXED frame and one of the PCK based earth orientation frames. Currently the supported PCK frames are IAU_EARTH and ITRF93. For study purposes you can normally define the EARTH_FIXED frame to coincide with the IAU_EARTH frame. If you have high precision requirements, you should define the EARTH_FIXED frame to coincide with the ITRF93 frame (or one of its successors). A regular schedule for the production of the ITRF93 PCK file has not yet been established. You will need to contact NAIF to obtain the current best ITRF93 PCK file. To establish the coincidence of the EARTH_FIXED and IAU_EARTH frames you need to create a text kernel with the following information in the "data" section of the text kernel TKFRAME_EARTH_FIXED_RELATIVE = 'IAU_EARTH' TKFRAME_EARTH_FIXED_SPEC = 'MATRIX' TKFRAME_EARTH_FIXED_MATRIX = ( 1 0 0 0 1 0 0 0 1 ) If you prefer to make the EARTH_FIXED frame coincide with the ITRF93 frame place the following lines in the text kernel. TKFRAME_EARTH_FIXED_RELATIVE = 'ITRF93' TKFRAME_EARTH_FIXED_SPEC = 'MATRIX' TKFRAME_EARTH_FIXED_MATRIX = ( 1 0 0 0 1 0 0 0 1 ) This text kernel along with the appropriate Earth PCK file must be loaded prior to retrieving the state of any of the stations relative to any frame other than 'EARTH_FIXED'. To load the one of the relationship defined above available to the SPICE system you should call the toolkit routine LDPOOL. CALL LDPOOL ( ) You will also need a planetary ephemeris and possibly a spacecraft or satellite ephemeris. Currently, JPL's state of the art planetary ephemeris is DE-403. Note, however, that your project may be using some other planetary ephemeris. You need to check with your project to determine the ephemeris that should be used for official project work. DE403 is available via anonymous ftp on NAIF's ftp server: naif-sun (ip address 128.149.126.11) in the directory pub/naif/generic_kernels/spk. Both binary and transfer format ephemerides are available. They are in the files: de403s.bsp ( binary format ) de403s.xsp ( transfer format ) de403s.cmt ( comments about de403s ) Accuracy -------------------------------------------------------- The coordinates used for the positions of the stations were taken from the DSN World-Wide-Web page http://dsnra.jpl.nasa.gov/Antennas.html on May 27, 1993. The coordinates and their accuracy as reported in the web page are: 1-sigma uncertainty(m) Antenna x(m) y(m) z(m) horiz vert DSS 12 -2350443.812 -4651980.837 +3665630.988 0.04 0.05 DSS 13 -2351112.452 -4655530.771 +3660912.823 0.04 0.05 DSS 14 -2353621.251 -4641341.542 +3677052.370 0.03 0.03 DSS 15 -2353538.790 -4641649.507 +3676670.043 0.03 0.03 DSS 16 -2354763.158 -4646787.462 +3669387.069 0.05 0.10 DSS 17 -2354730.357 -4646751.776 +3669440.659 0.05 0.10 DSS 23 -2354757.567 -4646934.675 +3669207.824 0.05 0.10 DSS 24 -2354906.495 -4646840.128 +3669242.317 0.05 0.10 DSS 25 -2355022.066 -4646953.636 +3669040.895 0.05 0.10 DSS 26 -2354890.967 -4647166.925 +3668872.212 0.05 0.10 DSS 27 -2349915.260 -4656756.484 +3660096.529 0.05 0.10 DSS 28 -2350101.849 -4656673.447 +3660103.577 0.05 0.10 DSS 33 -4461083.514 +2682281.745 -3674570.392 0.03 0.10 DSS 34 -4461124.698 +2682426.013 -3674375.098 1.00 5.00 DSS 42 -4460981.016 +2682413.525 -3674582.072 0.04 0.05 DSS 43 -4460894.585 +2682361.554 -3674748.580 0.03 0.03 DSS 45 -4460935.250 +2682765.710 -3674381.402 0.03 0.03 DSS 46 -4460828.619 +2682129.556 -3674975.508 0.04 0.04 Parkes -4554231.843 +2816758.983 -3454036.065 0.04 0.05 DSS 53 +4849330.118 -0360338.090 +4114758.758 0.05 0.10 DSS 54 +4849519.978 -0360641.651 +4114504.583 2.00 5.00 DSS 61 +4849245.211 -0360278.166 +4114884.445 0.04 0.05 DSS 63 +4849092.647 -0360180.569 +4115109.113 0.03 0.03 DSS 65 +4849336.730 -0360488.859 +4114748.775 0.03 0.03 DSS 66 +4849150.090 -0360479.109 +4115000.064 1.00 2.00 According to the Web page "cartesian coordinates are from IOM 335.1-95-027, dated 16 October 1995" References -------------------------------------------------------- See the web page or IOM cited above. Inquiries If you have any questions regarding this ephemeris contact Bill Taber btaber@spice.jpl.nasa.gov Phone (818) 354-4279 FAX (818) 393-6388 JPL MS 301/125L 4800 Oak Grove Drive Pasadena, CA 91109 or Nat Bachman nbachman@spice.jpl.nasa.gov Phone (818) 354-7454 FAX (818) 393-6388 JPL MS 301/125L 4800 Oak Grove Drive Pasadena, CA 91109 Appendix. Inputs to Pinpoint ========================================================================= \begindata SITES = ( 'DSS_12', 'DSS_13', 'DSS_14', 'DSS_15', 'DSS_16', 'DSS_17', 'DSS_23', 'DSS_24', 'DSS_25', 'DSS_26', 'DSS_27', 'DSS_28', 'DSS_33', 'DSS_34', 'DSS_42', 'DSS_43', 'DSS_45', 'DSS_46', 'DSS_53', 'DSS_54', 'DSS_61', 'DSS_63', 'DSS_65', 'DSS_66', 'PARKES' ) DSS_12_CENTER = 399 DSS_12_FRAME = 'EARTH_FIXED' DSS_12_IDCODE = 399012 DSS_12_XYZ = ( -2350.443812, -4651.980837, +3665.630988 ) DSS_13_CENTER = 399 DSS_13_FRAME = 'EARTH_FIXED' DSS_13_IDCODE = 399013 DSS_13_XYZ = ( -2351.112452, -4655.530771, +3660.912823 ) DSS_14_CENTER = 399 DSS_14_FRAME = 'EARTH_FIXED' DSS_14_IDCODE = 399014 DSS_14_XYZ = ( -2353.621251, -4641.341542, +3677.052370 ) DSS_15_CENTER = 399 DSS_15_FRAME = 'EARTH_FIXED' DSS_15_IDCODE = 399015 DSS_15_XYZ = ( -2353.538790, -4641.649507, +3676.670043 ) DSS_16_CENTER = 399 DSS_16_FRAME = 'EARTH_FIXED' DSS_16_IDCODE = 399016 DSS_16_XYZ = ( -2354.763158, -4646.787462, +3669.387069 ) DSS_17_CENTER = 399 DSS_17_FRAME = 'EARTH_FIXED' DSS_17_IDCODE = 399017 DSS_17_XYZ = ( -2354.730357, -4646.751776, +3669.440659 ) DSS_23_CENTER = 399 DSS_23_FRAME = 'EARTH_FIXED' DSS_23_IDCODE = 399023 DSS_23_XYZ = ( -2354.757567, -4646.934675, +3669.207824 ) DSS_24_CENTER = 399 DSS_24_FRAME = 'EARTH_FIXED' DSS_24_IDCODE = 399024 DSS_24_XYZ = ( -2354.906495, -4646.840128, +3669.242317 ) DSS_25_CENTER = 399 DSS_25_FRAME = 'EARTH_FIXED' DSS_25_IDCODE = 399025 DSS_25_XYZ = ( -2355.022066, -4646.953636, +3669.040895 ) DSS_26_CENTER = 399 DSS_26_FRAME = 'EARTH_FIXED' DSS_26_IDCODE = 399026 DSS_26_XYZ = ( -2354.890967, -4647.166925, +3668.872212 ) DSS_27_CENTER = 399 DSS_27_FRAME = 'EARTH_FIXED' DSS_27_IDCODE = 399027 DSS_27_XYZ = ( -2349.915260, -4656.756484, +3660.096529 ) DSS_28_CENTER = 399 DSS_28_FRAME = 'EARTH_FIXED' DSS_28_IDCODE = 399028 DSS_28_XYZ = ( -2350.101849, -4656.673447, +3660.103577 ) DSS_33_CENTER = 399 DSS_33_FRAME = 'EARTH_FIXED' DSS_33_IDCODE = 399033 DSS_33_XYZ = ( -4461.083514, +2682.281745, -3674.570392 ) DSS_34_CENTER = 399 DSS_34_FRAME = 'EARTH_FIXED' DSS_34_IDCODE = 399034 DSS_34_XYZ = ( -4461.124698, +2682.426013, -3674.375098 ) DSS_42_CENTER = 399 DSS_42_FRAME = 'EARTH_FIXED' DSS_42_IDCODE = 399042 DSS_42_XYZ = ( -4460.981016, +2682.413525, -3674.582072 ) DSS_43_CENTER = 399 DSS_43_FRAME = 'EARTH_FIXED' DSS_43_IDCODE = 399043 DSS_43_XYZ = ( -4460.894585, +2682.361554, -3674.748580 ) DSS_45_CENTER = 399 DSS_45_FRAME = 'EARTH_FIXED' DSS_45_IDCODE = 399045 DSS_45_XYZ = ( -4460.935250, +2682.765710, -3674.381402 ) DSS_46_CENTER = 399 DSS_46_FRAME = 'EARTH_FIXED' DSS_46_IDCODE = 399046 DSS_46_XYZ = ( -4460.828619, +2682.129556, -3674.975508 ) DSS_53_CENTER = 399 DSS_53_FRAME = 'EARTH_FIXED' DSS_53_IDCODE = 399053 DSS_53_XYZ = ( +4849.330118, -0360.338090, +4114.758758 ) DSS_54_CENTER = 399 DSS_54_FRAME = 'EARTH_FIXED' DSS_54_IDCODE = 399054 DSS_54_XYZ = ( +4849.519978, -0360.641651, +4114.504583 ) DSS_61_CENTER = 399 DSS_61_FRAME = 'EARTH_FIXED' DSS_61_IDCODE = 399061 DSS_61_XYZ = ( +4849.245211, -0360.278166, +4114.884445 ) DSS_63_CENTER = 399 DSS_63_FRAME = 'EARTH_FIXED' DSS_63_IDCODE = 399063 DSS_63_XYZ = ( +4849.092647, -0360.180569, +4115.109113 ) DSS_65_CENTER = 399 DSS_65_FRAME = 'EARTH_FIXED' DSS_65_IDCODE = 399065 DSS_65_XYZ = ( +4849.336730, -0360.488859, +4114.748775 ) DSS_66_CENTER = 399 DSS_66_FRAME = 'EARTH_FIXED' DSS_66_IDCODE = 399066 DSS_66_XYZ = ( +4849.150090, -0360.479109, +4115.000064 ) PARKES_CENTER = 399 PARKES_FRAME = 'EARTH_FIXED' PARKES_IDCODE = 399005 PARKES_XYZ = ( -4554.231843, +2816.758983, -3454.036065 )