Log file for SPACIT Version 7.1.1. ******************************************************************************** Comments From File: near_erosorbit_nlr_v1.bsp \beginlabel PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 1024 ^SPICE_KERNEL = "NEAR_EROSORBIT_NLR_V1.BSP" MISSION_NAME = "NEAR EARTH ASTEROID RENDEZVOUS" SPACECRAFT_NAME = "NEAR EARTH ASTEROID RENDEZVOUS" DATA_SET_ID = "NEAR-A-SPICE-6-EROS/ORBIT-V1.0" KERNEL_TYPE_ID = SPK PRODUCT_ID = "NEAR_EROSORBIT_NLR_V1.BSP" PRODUCT_CREATION_TIME = 2001-09-05T12:29:32 PRODUCER_ID = "NEAR-NLR/GSFC" MISSION_PHASE_NAME = EROS PRODUCT_VERSION_TYPE = ACTUAL PLATFORM_OR_MOUNTING_NAME = "N/A" START_TIME = 2000-03-03T18:05:00 STOP_TIME = 2001-01-27T01:20:00 SPACECRAFT_CLOCK_START_COUNT = "N/A" SPACECRAFT_CLOCK_STOP_COUNT = "N/A" TARGET_NAME = EROS INSTRUMENT_NAME = "N/A" NAIF_INSTRUMENT_ID = "N/A" SOURCE_PRODUCT_ID = "N/A" NOTE = "See comments in the file for details" OBJECT = SPICE_KERNEL INTERCHANGE_FORMAT = BINARY KERNEL_TYPE = EPHEMERIS DESCRIPTION = "NEAR spacecraft trajectory SPK file covering the Eros orbit phase of the mission created by merging reconstructed OD solution SPK files from the NLR Team/GSFC. " END_OBJECT = SPICE_KERNEL \endlabel NEAR Eros Orbit SPK file, NLR Team Solution =========================================================================== Created by Boris Semenov, NAIF/JPL, July 27, 2001. Objects in the Ephemeris -------------------------------------------------------- This file contains ephemeris data for the Near Earth Asteroid Rendezvous (NEAR) spacecraft. NAIF ID code for NEAR is -93. Approximate Time Coverage -------------------------------------------------------- This file covers almost the whole Eros orbit phase of the mission: COVERAGE BEGIN TIME (ET) COVERAGE END TIME (ET) ------------------------ ------------------------ 2000 MAR 03 18:06:04.184 2001 JAN 27 01:21:04.184 Because the propulsion maneuvers were not modeled in the trajectory determination process, the file contain numerous gaps that usually start at the exact times of the maneuvers and extend at least for the maneuver duration. Therefore, the actual coverage of the file consists of 37 disjoint intervals summarized in this table: COVERAGE BEGIN TIME (ET) COVERAGE END TIME (ET) ------------------------ ------------------------ 2000 MAR 03 18:06:04.184 2000 MAR 15 19:54:04.184 2000 MAR 15 20:04:04.184 2000 MAR 23 15:16:04.184 2000 MAR 23 15:26:04.184 2000 APR 01 22:16:04.184 2000 APR 02 02:09:04.184 2000 APR 11 21:16:04.184 2000 APR 11 21:26:04.184 2000 APR 22 17:46:04.184 2000 APR 22 17:56:04.184 2000 APR 30 16:11:04.184 2000 APR 30 16:21:04.184 2000 MAY 10 13:56:04.184 2000 MAY 10 14:06:04.184 2000 MAY 17 12:56:04.184 2000 MAY 17 13:06:04.184 2000 MAY 24 12:56:04.184 2000 MAY 24 13:06:04.184 2000 MAY 31 15:56:04.184 2000 MAY 31 16:06:04.184 2000 JUN 07 15:56:04.184 2000 JUN 07 16:06:04.184 2000 JUN 14 15:56:04.184 2000 JUN 14 16:06:04.184 2000 JUN 21 15:56:04.184 2000 JUN 21 16:06:04.184 2000 JUN 28 15:56:04.184 2000 JUN 28 16:06:04.184 2000 JUL 07 17:56:04.184 2000 JUL 07 18:06:04.184 2000 JUL 14 02:56:04.184 2000 JUL 14 03:06:04.184 2000 JUL 24 16:56:04.184 2000 JUL 24 17:06:04.184 2000 JUL 31 19:56:04.184 2000 JUL 31 20:06:04.184 2000 AUG 08 23:21:04.184 2000 AUG 09 02:31:04.184 2000 AUG 16 11:56:04.184 2000 AUG 16 12:06:04.184 2000 AUG 26 23:21:04.184 2000 AUG 27 04:06:04.184 2000 SEP 05 22:56:04.184 2000 SEP 06 04:06:04.184 2000 SEP 12 23:56:04.184 2000 SEP 13 00:06:04.184 2000 SEP 20 16:56:04.184 2000 SEP 20 17:06:04.184 2000 SEP 30 23:56:04.184 2000 OCT 01 00:06:04.184 2000 OCT 13 05:41:04.184 2000 OCT 13 05:51:04.184 2000 OCT 20 21:36:04.184 2000 OCT 20 21:46:04.184 2000 OCT 25 22:06:04.184 2000 OCT 26 17:46:04.184 2000 NOV 03 02:56:04.184 2000 NOV 03 03:06:04.184 2000 NOV 15 19:56:04.184 2000 NOV 15 20:06:04.184 2000 NOV 29 17:26:04.184 2000 NOV 29 17:36:04.184 2000 DEC 07 15:16:04.184 2000 DEC 07 15:26:04.184 2000 DEC 13 20:11:04.184 2000 DEC 13 20:21:04.184 2000 DEC 27 19:21:04.184 2000 DEC 27 19:31:04.184 2001 JAN 09 18:37:04.184 2001 JAN 09 18:47:04.184 2001 JAN 24 16:01:04.184 2001 JAN 24 16:11:04.184 2001 JAN 27 01:21:04.184 Status -------------------------------------------------------- This SPK file contains NEAR orbit reconstruction provided by Greg Neumann and Mark Torrence of the NEAR NLR Team, GSFC. Pedigree -------------------------------------------------------- The original SPK files used to make this file were generated as part of the NLR instrument data processing. The models and input data used in the orbit determination process are summarized in the Appendix 1 of these comments. The naming convention for the original SPK files was: BYYYYDOYEYYYYDOYG.BSP where the designation YYYYDOY refers to year and DOY of the file coverage begin and end. The complete list of SPK files the data from which have been included into this file is provided in the Appendix 2 of these comments. Contacts -------------------------------------------------------- If you have any questions regarding this data contact Boris V. Semenov, NAIF/JPL, +1 818 354-8136 bsemenov@spice.jpl.nasa.gov or members of the NEAR NLR Team: Gregory Neumann +1 301 614-6026 Gregory.Neumann@gsfc.nasa.gov Mark Torrence +1 301 794-5463 Mark.Torrence@gsfc.nasa.gov Appendix 1: Model and Input Data Description =========================================================================== The following description of the models and input data was provided by Mark Torrence on July 27, 2001: ---------------------------------------------------------------- The NEAR/Shoemaker Laser Rangefinder (NLR) science team calculated the orbit for the NEAR/Shoemaker spacecraft using the GEODYN and SOLVE orbit determination and geodetic parameter estimation software (1,2). Range and range rate tracking data from the Deep Space Network (DSN) were used in conjunction with the NLR altimeter measurements in the estimation procedure. Preprocessing components for the DSN data were adapted from those developed at GSFC for Mars Global Surveyor (MGS) preprocessing. Processing of the raw NLR data and NEAR attitude information from SPICE attitude "ck" kernels into formats used by GEODYN was implemented by the NLR team. A priori state vectors for NEAR were derived from the navigation SPICE "spk" files provided by the project. In addition, the position of 433 Eros and the planets were derived from the SPICE "spk" file "erosephem_1999004_2002181.bsp" and "de403s.bsp" respectively as provided by the NEAR project. The start and stop times for the 37 arcs for NEAR were defined to begin after and stop before orbital maneuvers or momentum dumps. Based upon information furnished by the project, the NEAR spacecraft shape was modeled as a twelve panel rectangular solid. NLR264 model was the a priori surface model for 433 Eros. In each arc, the initial non-singular keplerian state vector was estimated with a coefficient of solar radiation pressure. To mitigate the effect of 433 Eros position errors biases were estimated in every arc for each pass of DSN range data and one bias for the range rate for each tracking site. The range rate data were weighted at 0.1 hz, range data at 100 range units, and NLR at 500 m. The average recovered range bias was -13000 1 3000 m, and range rate bias spanned -0.002 to 0.001 hz. The median unweighted rms of fit for range rate was 0.016 hz, for range was 33 range units, and for NLR was 145 m. The 37 arcs had a total of 1,557,000 observations. The arcs were combined to simultaneously estimate a spherical harmonic model of the 433 Eros topography complete to degree and order 90, the gravity field to degree and order 6, and the GM and rotation pole orientation to produce the NLR393 model. (1) D. D. Rowlands et al., "GEODYN II System Description" (Hughes-STX Contractor Report, 1993). (2) J. J. McCarthy et al., "SOLVE Systems Descriptions and Operations Manuals" (NASA GSFC and Hughes/STX Contractor Report, 1994). ---------------------------------------------------------------- Appendix 2: Original SPK Files =========================================================================== The data from the following original files was included into this file: Original SPK File Start Time (ET) Stop Time (ET) ----------------- -------------------- -------------------- B2000063E2000075G 2000 MAR 03 18:06:04 2000 MAR 15 19:54:04 B2000075E2000083G 2000 MAR 15 20:04:04 2000 MAR 23 15:16:04 B2000083E2000092G 2000 MAR 23 15:26:04 2000 APR 01 22:16:04 B2000093E2000102G 2000 APR 02 02:09:04 2000 APR 11 21:16:04 B2000102E2000113G 2000 APR 11 21:26:04 2000 APR 22 17:46:04 B2000113E2000121G 2000 APR 22 17:56:04 2000 APR 30 16:11:04 B2000121E2000131G 2000 APR 30 16:21:04 2000 MAY 10 13:56:04 B2000131E2000138G 2000 MAY 10 14:06:04 2000 MAY 17 12:56:04 B2000138E2000145G 2000 MAY 17 13:06:04 2000 MAY 24 12:56:04 B2000145E2000152G 2000 MAY 24 13:06:04 2000 MAY 31 15:56:04 B2000152E2000159G 2000 MAY 31 16:06:04 2000 JUN 07 15:56:04 B2000159E2000166G 2000 JUN 07 16:06:04 2000 JUN 14 15:56:04 B2000166E2000173G 2000 JUN 14 16:06:04 2000 JUN 21 15:56:04 B2000173E2000180G 2000 JUN 21 16:06:04 2000 JUN 28 15:56:04 B2000180E2000189G 2000 JUN 28 16:06:04 2000 JUL 07 17:56:04 B2000189E2000196G 2000 JUL 07 18:06:04 2000 JUL 14 02:56:04 B2000196E2000206G 2000 JUL 14 03:06:04 2000 JUL 24 16:56:04 B2000206E2000213G 2000 JUL 24 17:06:04 2000 JUL 31 19:56:04 B2000214E2000221G 2000 JUL 31 20:06:04 2000 AUG 08 23:21:04 B2000222E2000229G 2000 AUG 09 02:31:04 2000 AUG 16 11:56:04 B2000229E2000240G 2000 AUG 16 12:06:04 2000 AUG 26 23:21:04 B2000240E2000250G 2000 AUG 27 04:06:04 2000 SEP 05 22:56:04 B2000250E2000257G 2000 SEP 06 04:06:04 2000 SEP 12 23:56:04 B2000257E2000264G 2000 SEP 13 00:06:04 2000 SEP 20 16:56:04 B2000264E2000275G 2000 SEP 20 17:06:04 2000 SEP 30 23:56:04 B2000275E2000287G 2000 OCT 01 00:06:04 2000 OCT 13 05:41:04 B2000287E2000294G 2000 OCT 13 05:51:04 2000 OCT 20 21:36:04 B2000294E2000299G 2000 OCT 20 21:46:04 2000 OCT 25 22:06:04 B2000300E2000308G 2000 OCT 26 17:46:04 2000 NOV 03 02:56:04 B2000308E2000320G 2000 NOV 03 03:06:04 2000 NOV 15 19:56:04 B2000320E2000334G 2000 NOV 15 20:06:04 2000 NOV 29 17:26:04 B2000334E2000342G 2000 NOV 29 17:36:04 2000 DEC 07 15:16:04 B2000342E2000348G 2000 DEC 07 15:26:04 2000 DEC 13 20:11:04 B2000348E2000362G 2000 DEC 13 20:21:04 2000 DEC 27 19:21:04 B2000362E2001009G 2000 DEC 27 19:31:04 2001 JAN 09 18:37:04 B2001009E2001024G 2001 JAN 09 18:47:04 2001 JAN 24 16:01:04 B2001024E2001027G 2001 JAN 24 16:11:04 2001 JAN 27 01:21:04 ********************************************************************************