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SOHO Recovery Updates |
The heating phases of the batteries charging/heating cycles have been reduced by 2 hours. The cycles are now 2 hr charging and 5 hr heating. With these settings the batteries are expected to be fully charged for the attitude recovery maneuver by 01:00 UT tomorrow. Due to this change, both battery temperature and voltage have raised slightly while propulsion subsystem temperatures have decreased a little bit.
The payload RTU has been switched on briefly today at 16:00 UT to take a reading of the payload module thermistors. The payload temperatures can be found in the table included below.
After reviewing the simulation run today, it was decided to run the attitude recovery maneuver tomorrow. The solution chosen to recover the attitude of the spacecraft consists of (times are subject to change):
Time UT Description
1. 06:00 Additional warming up of the propulsion subsystem.
2. 08:00 Intermediate check of telemetry.
3. 10:30 Adjustment of Sun heating mode before maneuvers.
4. 12:00 Thrusters tests.
5. 12:30 Thruster 4B despin calibration.
6. 13:05 Thruster 4B despin 1 (down to 2.4 deg/s).
7. 13:50 Data collection and procedure uploading.
8. 14:10 Data evaluation.
9. FOT load update prior to despin 2.
10. 15:15 Thruster 4B despin 2 (down to 0.9 deg/s).
11. 16:35 Switch on FDE and enable/reset min/max monitoring.
12. 17:09 Data evaluation.
13. Battery management.
14. 17:14 Preparation of ESR.
15. Check spacecraft status before ESR.
16. 18:09 Go for ESR given subsystem by subsystem.
17. 18:10 Thermal control management.
18. Upload timetags to enable standard monitoring functions.
T1 ESR trigger.
19. T1+3 ESR without on board roll control.
20. Set up payload configuration (RTU, PPDU on).
21. Trigger COBS reboot and reset thermal control.
22. Thermal adjustment after ESR (including EXP subs heaters).
23. Spin up and selection of gyro for ground roll control.
Every step has criteria for success and contingency plans defined.
After the end of these activities, the spacecraft will have on board Sun pointing control. The roll rate will be controlled from ground.
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PLM Temperatures on 9 August, 28 August, 9 September and 15 September 1998
MNEMONIC Limit Temperature [deg C]
8/9/98 8/28/98 9/9/98 15/9/98
CDS
QTCI1A 10/30 78.57 48.23 15.14 -4.17
QTCI1B 10/30 78.57 47.60 14.85 -4.47
QTCR1 5/35 1.91 -6.54 -13.98 -18.83
QTCR2 6/30 35.28 13.13 -3.88 -12.70
QTCR3 6/34 41.92 12.56 -9.50 -19.20
CELIAS
QTFI1A -15/35 42.78 22.95 6.93 -4.56
QTFI1B -15/35 41.91 22.95 7.32 -3.57
QTFI2A -40/40 35.37 22.95 13.96 1.46
QTFI2B -40/40 34.93 22.95 13.96 1.07
QTFI3A -15/35 41.91 24.12 6.93 -3.07
QTFI3B -15/35 41.91 23.73 6.54 -3.57
QTFR1 5/35 3.35 -4.47 -11.74 -16.63
QTFR2 5/35 3.92 -5.07 -12.38 -18.10
QTFR3 5/35 9.96 -0.68 -9.50 -15.90
QTFR4 7/30 16.74 1.91 -9.50 -17.00
QTFR5 8/36 -5.65 -13.02 -18.83 -21.40*
Q11 5/35 10.54 -1.54 -11.10 -17.37
CEPAC
QTHI1A 10/25 -21.40* -21.40* -21.40* -21.40*
QTHI1B 10/25 -21.40* -21.40* -21.40* -21.40*
QTHI2 -13/21 -21.67 -22.22 -24.44 -26.11
QTHI3 0/30 -19.57 -15.58 -16.27 -17.73
QTHR1 5/35 -11.10 -15.58 -20.30 -21.40*
QTHR2 8/31 -4.47 -11.74 -18.10 -21.40*
QTHR3 -3/34 -21.40* -21.40* -21.40* -21.40*
QTHR4 4/33 -11.10 -17.00 -21.40* -21.40*
QTHR5 5/35 -7.43 -13.98 -19.57 -21.40*
GOLF
QTGI1A 5/40 -21.40* -16.27 -18.47 -21.40*
QTGI1B 5/40 -21.40* -16.27 -18.10 -21.40*
QTGR1 5/35 3.64 -5.06 -12.38 -17.73
QTGR2 10/25 39.39 14.56 -2.40 -11.42
QTGR3 5/35 40.03 12.83 -5.65 -14.94
LASCO/EIT
QTLI1A 5/30 33.19 22.95 14.35 8.49
QTLI1B 5/30 33.62 23.72 15.13 9.28
QTLI2A 10/30 -49.20* -49.20* -46.17 -46.17
QTLI2B 10/30 -49.20* -47.68 -44.66 -44.66
QTLI3A -10/20 -49.20* -49.20* -47.69 -46.17
QTLI3B -10/20 -49.20* -49.20* -49.20* -47.69
QTLR1 5/35 -3.58 -11.42 -16.63 -20.67
QTLR2 5/35 -15.26 -20.67 -21.40* -21.40
QTLR3 5/35 4.21 -3.58 -10.46 -15.58
MDI
QTMI1A 10/35 -21.40* -18.47 -20.67 -21.03
QTMI1B 10/35 -21.40* -15.58 -17.73 -18.10
QTMI1C 10/41 -21.40* -16.63 -18.83 -19.20
QTMI1D -105/40 -53.33 -43.33 -48.33 -46.67
QTMI2 0/40 -22.15 -23.60 -24.32 -25.05
QTMR1 5/35 -2.40 -9.20 -14.94 -19.57
QTMR2 5/35 -3.58 -8.91 -12.70 -15.90
SUMER
QTSI1A 15/27 -21.40* -21.40* -21.40* -21.40*
QTSI1B 15/27 -21.40* -21.40* -21.40* -21.40*
QTSI2A 5/25 -21.40* -19.93 -21.40* -21.40*
QTSI2B 5/25 -21.40* -19.56 -21.03 -21.40*
QTSR1 5/35 -0.96 -8.91 -14.94 -19.20
QTSR2 5/34 -16.27 -21.40* -21.40* -21.40*
QTSR3 2/27 -13.98 -19.57 -21.40* -21.40*
SWAN
QTNI1A 5/30 44.45 37.50 30.09 23.04
QTNI1B 5/30 45.71 39.39 31.93 24.90
QTNI2A 5/30 -21.40* -21.40* -21.40* -21.40*
QTNI2B 5/30 -21.40* -21.40* -21.40* -21.40*
QTNR1 5/35 29.34 20.45 11.11 3.92
QTNR2 5/35 -21.40* -21.40* -21.40* -21.40*
QTNR3 6/31 -13.66 -19.57 -21.40* -21.40*
UVCS
QTUI1A 0/40 -5.65 -6.54 -8.61 -12.06
QTUI1B 0/40 -5.36 -6.25 -8.02 -11.42
QTUR1 5/35 -5.06 -9.82 -15.58 -20.30
QTUR2 5/30 37.13 11.11 -8.32 -17.73
VIRGO
QTVR1 3/30 -9.50 -15.58 -21.03 -21.40*
QTVR2 5/33 -18.83 -21.40* -21.40* -21.40*
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Note: * means: end of sensor measurement range