PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM" TARGET_NAME = MARS DATA_SET_ID = "MGS-M-RSS-1-MAP-V1.0" PRODUCT_TYPE = AGK MISSION_NAME = "MARS GLOBAL SURVEYOR" INSTRUMENT_HOST_NAME = "MARS GLOBAL SURVEYOR" ORIGINAL_PRODUCT_ID = "mgs_hga_map4.bc" PRODUCT_ID = "9321039A.AGK" FILE_NAME = "9321039A.AGK" START_TIME = 1999-11-17T00:00:06.661Z STOP_TIME = 2000-02-08T23:59:33.770Z PRODUCT_CREATION_TIME = 2000-02-25T00:00:00.000Z PRODUCER_ID = NAIF ^DESCRIPTION = "TK_FTP.TXT" NOTE = " MGS HGA Gimbals Orientation CK File for Mapping, Cycles 10-12 =========================================================================== Created by Boris Semenov, NAIF/JPL, February 25, 2000 Orientation Data in the File -------------------------------------------------------- This file contains orientation and angular rate data for the Mars Global Surveyor (MGS) High Gain Antenna (HGA) Elevation and Azimuth gimbal frames. The orientation of the 'MGS_HGA_EL_GIMBAL' is given with respect to the 'MGS_HGA_HINGE' frame; orientation of the 'MGS_HGA_AZ_GIMBAL' is given with respect to the 'MGS_HGA_EL_GIMBAL' frame. Status -------------------------------------------------------- This file was created by merging daily HGA Gimbal CK files produced by the NAIF, JPL. No timing or any other correction was applied to the original data during merge process. Pedigree -------------------------------------------------------- The original CK files used to create this file were officially delivered to the MGS SPICE Server by NAIF, JPL. These files contained orientation of the HGA gimbal frames. The orientation was computed on the ground from the HGA gimbal angles extracted from the spacecraft engineering telemetry. HGA gimbal angle data sampling rate was once every 32 seconds. The individual daily files were merged together to provide complete coverage on a mission phase basis. A table containing the complete list of original CK files from which data were included in this file is provided at the end of these comments. Approximate Time Coverage -------------------------------------------------------- This file covers 10th, 11th and 12th 28-day mapping cycles of the Mapping phase of the mission: COVERAGE BEGIN TIME (UTC): 1999 NOV 17 00:00:06.661 COVERAGE END TIME (UTC): 2000 FEB 08 23:59:33.769 This file is a type 3 CK file which provides linear interpolation between orientation data points extracted from telemetry. Such interpolation is not applied to the whole coverage of the file but only inside intervals where enough gimbal telemetry data was available and data points were close to each other in time for such interpolation to make sense. Given that nominal gimbal telemetry rate was once every 32 seconds the duration of the longest interval over which the data may be interpolated was set to 300 seconds, i.e. interpolation was enabled only over an eight point drop-out. For all requests for the data falling between two adjacent data points separated by more than 300 seconds the SPICELIB CK readers will return a logical flag stating ``POINTING NOT FOUND''. Tables containing the complete list of valid interpolation intervals for the AZ and EL frame data in the file are provided at the end of these comments. Since AZ and EL gimbal values were extracted from telemetry by two subsequent Telemetry Data System queries, returned sets of points for them, and thus resulting coverage intervals, may be different. Note Regarding Orientation -------------------------------------------------------- The orientation of the 'MGS_HGA_EL_GIMBAL' is given with respect to the 'MGS_HGA_HINGE' frame and was computed from the gimbal geometry and telemetered gimbal angles as follows: -- the ``MGS_HGA_HINGE'' (-94070) frame was rotated by -85 degrees about +Z axis to align its axes of the with axes of the ``MGS_HGA_EL_GIMBAL'' (-94071) frame in EL=0 position -- then rotation by the EL angle about +Z axis was applied. The orientation of the 'MGS_HGA_AZ_GIMBAL' is given with respect to the 'MGS_HGA_EL_GIMBAL' frame and was computed from the gimbal geometry and telemetered gimbal angles as follows: -- the ``MGS_HGA_EL_GIMBAL'' (-94071) frame was rotated first by +90 degrees about +Y and then by +180 degrees about +Z axis to align its axes with the axes of the ``MGS_HGA_AZ_GIMBAL'' (-94072) frame in AZ=0 positions; -- then rotation by AZ angle about +Z axis was applied. Note Regarding Angular Rates -------------------------------------------------------- Since MGS s/c engineering telemetry doesn't contain angular rate data for the gimbals, the angular rates stored in this file were computed from the orientation information. The angular rate for each orientation point was computed as average of two rates -- constant angular rate that would rotate from previous point to that point and constant angular rate that would rotate from that point to the next point. Because angular rates stored in two adjacent points in most cases are not the same, and CK readers lineraly interpolate between them, the output angular rates in general are almost never constant between any two adjacent data points stored in the file. Usage Note -------------------------------------------------------- In order to use this file an MGS SCLK file containing coefficients mapping MGS on-board time to ET and frame definitions for the MGS spacecraft and HGA hinge and gimbal frames must be loaded into a user's program. Related Kernels -------------------------------------------------------- This file was created with LSK file naif0007.tls and MGS SCLK file MGS_SCLKSCET.00030.tsc. Contacts -------------------------------------------------------- If you have any question regarding this data contact NAIF at JPL: Charles H. Acton, Jr (818)-354-3869 chuck.acton@jpl.nasa.gov Boris V. Semenov (818)-354-8136 boris.semenov@jpl.nasa.gov Appendix 1: List of the original CK files -------------------------------------------------------- mgs_hga_ck_1999-11-17.bc mgs_hga_ck_1999-11-18.bc mgs_hga_ck_1999-11-19.bc mgs_hga_ck_1999-11-20.bc mgs_hga_ck_1999-11-21.bc mgs_hga_ck_1999-11-22.bc mgs_hga_ck_1999-11-23.bc mgs_hga_ck_1999-11-24.bc mgs_hga_ck_1999-11-25.bc mgs_hga_ck_1999-11-26.bc mgs_hga_ck_1999-11-27.bc mgs_hga_ck_1999-11-28.bc mgs_hga_ck_1999-11-29.bc mgs_hga_ck_1999-11-30.bc mgs_hga_ck_1999-12-01.bc mgs_hga_ck_1999-12-02.bc mgs_hga_ck_1999-12-03.bc mgs_hga_ck_1999-12-04.bc mgs_hga_ck_1999-12-05.bc mgs_hga_ck_1999-12-06.bc mgs_hga_ck_1999-12-07.bc mgs_hga_ck_1999-12-08.bc mgs_hga_ck_1999-12-09.bc mgs_hga_ck_1999-12-10.bc mgs_hga_ck_1999-12-11.bc mgs_hga_ck_1999-12-12.bc mgs_hga_ck_1999-12-13.bc mgs_hga_ck_1999-12-14.bc mgs_hga_ck_1999-12-15.bc mgs_hga_ck_1999-12-16.bc mgs_hga_ck_1999-12-17.bc mgs_hga_ck_1999-12-18.bc mgs_hga_ck_1999-12-19.bc mgs_hga_ck_1999-12-20.bc mgs_hga_ck_1999-12-21.bc mgs_hga_ck_1999-12-22.bc mgs_hga_ck_1999-12-23.bc mgs_hga_ck_1999-12-24.bc mgs_hga_ck_1999-12-25.bc mgs_hga_ck_1999-12-26.bc mgs_hga_ck_1999-12-27.bc mgs_hga_ck_1999-12-28.bc mgs_hga_ck_1999-12-29.bc mgs_hga_ck_1999-12-30.bc mgs_hga_ck_1999-12-31.bc mgs_hga_ck_2000-01-01.bc mgs_hga_ck_2000-01-02.bc mgs_hga_ck_2000-01-03.bc mgs_hga_ck_2000-01-04.bc mgs_hga_ck_2000-01-05.bc mgs_hga_ck_2000-01-06.bc mgs_hga_ck_2000-01-07.bc mgs_hga_ck_2000-01-08.bc mgs_hga_ck_2000-01-09.bc mgs_hga_ck_2000-01-10.bc mgs_hga_ck_2000-01-11.bc mgs_hga_ck_2000-01-12.bc mgs_hga_ck_2000-01-13.bc mgs_hga_ck_2000-01-14.bc mgs_hga_ck_2000-01-15.bc mgs_hga_ck_2000-01-16.bc mgs_hga_ck_2000-01-17.bc mgs_hga_ck_2000-01-18.bc mgs_hga_ck_2000-01-19.bc mgs_hga_ck_2000-01-20.bc mgs_hga_ck_2000-01-21.bc mgs_hga_ck_2000-01-22.bc mgs_hga_ck_2000-01-23.bc mgs_hga_ck_2000-01-24.bc mgs_hga_ck_2000-01-25.bc mgs_hga_ck_2000-01-26.bc mgs_hga_ck_2000-01-27.bc mgs_hga_ck_2000-01-28.bc mgs_hga_ck_2000-01-29.bc mgs_hga_ck_2000-01-30.bc mgs_hga_ck_2000-01-31.bc mgs_hga_ck_2000-02-01.bc mgs_hga_ck_2000-02-02.bc mgs_hga_ck_2000-02-03.bc mgs_hga_ck_2000-02-04.bc mgs_hga_ck_2000-02-05.bc mgs_hga_ck_2000-02-06.bc mgs_hga_ck_2000-02-07.bc mgs_hga_ck_2000-02-08.bc Appendix 2: Interpolation Intervals for HGA EL and AZ gimbals -------------------------------------------------------- Table contains start and stop UTC time for each interval. 1999-11-17T00:00:06.661 1999-11-18T17:53:10.642 1999-11-18T18:02:46.642 1999-11-19T00:11:18.640 1999-11-19T00:22:30.639 1999-11-21T11:34:30.613 1999-11-21T11:43:34.613 1999-11-23T07:10:30.594 1999-11-23T07:23:18.594 1999-11-24T08:36:22.583 1999-11-24T08:55:02.583 1999-11-25T10:07:34.572 1999-11-25T10:13:58.572 1999-11-26T10:16:06.561 1999-11-26T10:27:50.561 1999-11-30T04:43:18.521 1999-11-30T05:33:26.521 1999-12-02T05:43:34.499 1999-12-02T05:49:26.499 1999-12-02T21:12:06.493 1999-12-02T22:13:26.492 1999-12-03T16:50:46.484 1999-12-03T17:00:22.484 1999-12-06T07:31:18.456 1999-12-06T07:36:38.456 1999-12-06T11:59:34.454 1999-12-06T12:09:10.454 1999-12-08T06:47:34.435 1999-12-08T07:03:34.435 1999-12-08T07:03:34.435 1999-12-08T07:21:42.435 1999-12-08T11:17:26.434 1999-12-08T11:43:34.433 1999-12-09T02:10:46.427 1999-12-09T02:19:18.427 1999-12-12T04:41:10.394 1999-12-12T05:11:34.394 1999-12-16T15:48:22.347 1999-12-16T15:55:18.347 1999-12-19T05:59:34.319 1999-12-19T06:10:14.319 1999-12-19T17:58:30.314 1999-12-19T18:04:54.314 1999-12-19T20:59:18.313 1999-12-19T21:07:18.313 1999-12-20T03:21:42.310 1999-12-20T03:49:58.310 1999-12-22T11:44:06.285 1999-12-22T11:54:14.285 1999-12-26T00:26:14.248 1999-12-26T00:44:22.248 1999-12-28T01:04:38.226 1999-12-28T01:12:38.226 1999-12-28T05:00:54.225 1999-12-28T05:08:54.225 1999-12-28T05:21:10.224 1999-12-28T05:36:38.224 1999-12-28T11:58:30.221 1999-12-28T12:13:26.221 1999-12-28T21:52:06.217 1999-12-28T22:13:26.217 1999-12-29T00:55:02.216 1999-12-29T01:04:06.216 1999-12-29T20:23:02.207 1999-12-29T20:34:46.207 1999-12-30T09:32:54.201 1999-12-30T09:45:10.201 1999-12-30T20:39:34.196 1999-12-30T20:58:46.196 2000-01-02T12:57:10.168 2000-01-02T13:05:42.168 2000-01-03T02:16:38.162 2000-01-03T02:25:10.162 2000-01-06T11:38:46.126 2000-01-06T11:49:26.126 2000-01-09T01:27:02.099 2000-01-09T02:02:14.099 2000-01-09T03:12:06.098 2000-01-09T03:56:22.098 2000-01-09T05:09:58.097 2000-01-09T05:54:46.097 2000-01-09T05:59:34.097 2000-01-09T06:23:34.097 2000-01-09T14:11:18.093 2000-01-09T14:20:22.093 2000-01-11T18:31:34.070 2000-01-11T18:51:50.070 2000-01-13T22:52:54.047 2000-01-13T23:37:42.047 2000-01-14T02:53:26.046 2000-01-14T03:06:14.045 2000-01-14T04:45:26.045 2000-01-14T04:51:18.045 2000-01-15T22:25:42.026 2000-01-15T22:41:42.026 2000-01-16T19:30:14.017 2000-01-16T19:40:54.017 2000-01-17T05:59:34.012 2000-01-17T06:19:18.012 2000-01-17T11:32:54.010 2000-01-17T11:55:50.010 2000-01-17T11:57:58.010 2000-01-17T12:09:10.010 2000-01-18T02:26:46.003 2000-01-18T02:32:38.003 2000-01-18T02:56:38.003 2000-01-18T03:07:18.003 2000-01-20T21:32:21.974 2000-01-20T21:37:41.974 2000-01-21T11:01:25.968 2000-01-21T11:11:01.968 2000-01-23T12:31:33.946 2000-01-23T12:41:41.946 2000-01-24T07:39:17.938 2000-01-24T07:45:09.938 2000-01-24T09:03:01.937 2000-01-24T09:12:05.937 2000-01-24T16:32:37.934 2000-01-24T16:55:33.934 2000-01-24T18:09:41.933 2000-01-24T18:17:09.933 2000-01-25T12:24:37.925 2000-01-25T12:49:09.925 2000-01-25T15:16:21.924 2000-01-25T15:30:13.924 2000-01-26T01:03:33.919 2000-01-26T01:36:37.919 2000-01-26T22:39:33.910 2000-01-26T23:23:49.909 2000-01-28T00:26:13.898 2000-01-28T00:54:29.898 2000-01-29T08:51:49.884 2000-01-29T09:09:25.884 2000-01-29T10:15:01.884 2000-01-29T10:25:09.883 2000-01-29T18:14:29.880 2000-01-29T18:22:29.880 2000-01-31T15:54:13.860 2000-01-31T16:07:01.860 2000-02-03T06:39:01.831 2000-02-03T06:56:05.831 2000-02-07T10:26:45.786 2000-02-07T10:35:17.786 2000-02-08T00:23:01.779 2000-02-08T00:46:29.779 2000-02-08T00:50:13.779 2000-02-08T01:38:45.779 2000-02-08T02:02:45.779 2000-02-08T02:09:09.778 2000-02-08T10:26:45.775 2000-02-08T11:08:53.774 2000-02-08T14:34:13.773 2000-02-08T15:01:25.773 2000-02-08T23:59:33.769 " END