PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2002-02-28 NOTE = "MGS RST Instrument Health Report HEA2059A.TXT" END_OBJECT = TEXT END Miscellaneous ============= Contact has been lost with MGS. Late yesterday Gene Brower, Mars Global Surveyor Mission Manager, circulated the (slightly edited) report below: At approximately 02-058/19:24 (SCET), a new Y-axis Gyro scale factor update was uploaded and a STAREX reset (part of the scale factor update process) was commanded. The star identification process began to show convergence problems and the unidentified star counter started to increment, displaying higher than normal values. When the downlink signal returned after occultation, AGC levels were lower than expected and telemetry became limited. The downlink signal continued to degrade to the point the carrier signal was not seen by the DSN stations (both 34-m and 70-m). When the star processing problems were first noticed, contingency commands were built to command the spacecraft to the nadir orientation, so that MHSA inputs could be included in the attitude determination. Commands to return to nadir were radiated numerous times over both 34-m and 70-m DSN stations but receipt of these commands was not confirmed by the spacecraft. With lack of a downlink carrier signal and after continued attempts to return MGS to a nadir orientation, a decision was made to stop commanding MGS in the hopes that the problem would be corrected autonomously or MGS would enter C-mode. Aseel Anabtawi, MGS RST Operations Engineer, adds that the last successful occultation measurement was 13297i over DSS-65. 13298e over DSS-65 and DSS-15 had a very weak signal, and so did 13298i over DSS-15. All measurements that followed had no signal. Engineering Data ================ Engineering Data Statistical Summary from CSV2STAT: First SCET: 2002-02-26T00:00:04.806 Last SCET: 2002-02-26T23:59:56.793 CHANNL CHANNEL TITLE DN-LO DN-HI EU-LO EU-HI EU-AVG/STDEV RECDS ------ ------------- ----- ----- --------- --------- ---------/-------- ----- F-0190 HGA_AZ_ANG 3211 3266 7.84E-01 7.97E-01 7.89E-01/3.77E-05 2698 F-0195 HGA_EL_ANG -11233 11089 -2.74E+00 2.71E+00 7.08E-01/3.50E-02 2698 L-0034 MOT1_RANGING 0 0 5400 L-0036 MOT1_TLM_MOD 0 0 5400 L-0037 MOT1_USO_ENA 0 0 5400 L-0044 MOT2_RANGING 1 1 5400 L-0046 MOT2_TLM_MOD 0 1 5400 L-0047 MOT2_USO_ENA 1 1 5400 L-0053 RF_SW_OSC 2 2 5400 L-0060 TWTA1_FILMNT 0 0 5400 L-0061 TWTA1_HV 0 0 5400 L-0070 TWTA2_FILMNT 1 1 5400 L-0071 TWTA2_HV 0 1 5400 L-0080 USO_PWR 0 0 5400 L-0090 KaBLE_STAT 0 0 5400 L-0091 KaBLE_ENABLE 1 1 5400 L-0111 MOT1_RCV_AGC 255 255 -1.53E+02 -1.53E+02 -1.53E+02/8.20E-07 5400 L-0121 MOT2_RCV_AGC 157 255 -1.53E+02 -1.26E+02 -1.47E+02/1.41E-01 5400 L-0131 TWTA1_HLX_I 0 1 -3.84E-02 -1.85E-02 -3.83E-02/1.72E-05 5400 L-0132 TWTA1_ANOD_V 0 1 -1.00E+03 -1.00E+03 -1.00E+03/1.13E-02 675 L-0141 TWTA2_HLX_I 17 42 2.86E-01 7.85E-01 5.72E-01/2.76E-03 5400 L-0142 TWTA2_ANOD_V 62 229 -8.64E+02 -5.30E+02 -7.17E+02/6.26E+00 675 L-0200 USO_REG_V 203 205 4.06E+00 4.10E+00 4.08E+00/1.99E-04 675 L-0201 USO_OVEN_V 129 132 2.58E+00 2.64E+00 2.61E+00/3.56E-04 675 T-0302 EPC1_T 180 196 -4.19E+00 2.50E+00 -6.04E-01/7.78E-02 675 T-0303 EPC2_T 179 192 -2.43E+00 2.90E+00 3.37E-01/5.95E-02 675 T-0310 RF_ISOLTR1_T 228 233 -6.05E+00 -2.48E-02 -2.73E+00/1.24E-02 5400 T-0311 RF_ISOLTR2_T 220 233 -6.05E+00 7.73E+00 2.00E+00/5.01E-02 5400 T-0312 TWT1_T 227 232 -4.77E+00 1.06E+00 -1.57E+00/4.62E-02 675 T-0313 TWT2_T 214 233 -6.05E+00 1.23E+01 4.26E+00/2.31E-01 675 T-0315 USO_T 134 138 2.23E+01 2.35E+01 2.30E+01/9.01E-03 675 T-0316 KA_AMP_T 214 219 8.56E+00 1.23E+01 1.06E+01/3.46E-02 675 L-0200, L-0201, and T-0315 are nominal. Open Loop Data ============== Data Collection --------------- We have transferred the following RSR open loop data to Stanford: YYYY/DDD DSS RSR RSR CH KSPS BT REC RECS RSR MAX START STOP ID RS LEN FILE NAME SNR -------- --- -------- -------- --- -- ---- -- ----- ----- ------------ ----- 2002/057 15 20:59:00 21:08:00 3 1 2 16 8260 541 2057205J.RSR 51.3 2002/057 15 21:38:00 21:47:00 3 1 2 16 8260 541 20572138.RSR 50.7 2002/057 15 22:57:00 23:05:00 3 1 2 16 8260 481 20572257.RSR 51.4 2002/057 15 23:35:00 23:44:00 3 1 2 16 8260 541 20572335.RSR 51.3 2002/058 15 00:55:00 01:03:00 3 1 2 16 8260 481 20580055.RSR 51.0 2002/058 15 01:33:00 01:42:00 3 1 2 16 8260 541 20580133.RSR 50.3 Anomalies --------- Data collected from DSS 15 occultations 13285i through 13288e (start times 2002/057-20:59:00 through 2002/058-01:33:00) has continued ~2 dB low SNR due to the substitution of a HEMPT front end for the normal laser. Data collected from DSS 15 occultation 13286e (start time 2002/057-21:38:00) had a -0.5 dB drop in the free-space carrier amplitude over 5 minutes. The following occultation was collected at two different antennas: Occultation Start Date/Time DSS #1 DSS #2 ----------- ----------------- ------ ------ 13285i 2002/057-20:59:00 65 15 Closed Loop Data ================ Data Collection --------------- We have obtained the following files from OSCAR: Original File Name Name on SOPC ------------------------------------ ------------ ODF: 02057O058_10S.SJO;1 2057058A.ODF Ancillary Data ============== Data Collection --------------- We have obtained the following files from the FIS: Original File Name Name on SOPC ------------------------------------ ------------ OPT: optg_m_020227_OD13290-13297_13546_V1 2058079A.OPT SAK: mgs_solar_array_2002-057.ck 2057057A.SAK SPK: spk_m_020227_OD13290-13297_13546_V1 2058079A.SPK TCK: mgs_spice_c_kernel_2002-057.ck 2057057A.TCK We have obtained the following files from NAIF: Original File Name Name on SOPC ------------------------------------ ------------ AGK: mgs_hga_ck_2002-02-18.bc 2049049A.AGK TCK: mgs_sc_ext3.bc 1178261A.TCK TCK: mgs_sc_ext4.bc 1262345A.TCK The two TCK files collected from NAIF are composites, covering 2-3 months each. Because of their size, these files will remain on-line only briefly.