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SFI: 70 | Ap index:  2  | Kp index:  0  ( 0 @16:45,  0 @19:45)| X-ray flux:  A1.6 
SW: Density= 5.6 p/cm3 | Speed= 333.4 km/s | Temp=32(x1000)K
IMF: Bx=2.0nT | By=-5.4nT | Bz= 3.3 nT | Bt= 6.6 nT | Lat= 29.5 ° | Lon=290.6°
Sunspots: 12 | Area: 10 10-6/Hemi | New regions: 0
[i]X-ray flares: C=0 M=0 X=0 | Optical flares: M1=0 M2=0 M3=0 | Sub-flares=0
Five telemetry frames were received on Wednesday, August 31. With a good signal level, -159 to -164 dBm and a ~3 minute period, there was continuous communications with the TWTA on for 30 minutes. Subsequent analysis showed that the telemetry from the PDU was stale, so there was no sun vector. From the one sample, the battery appears to be charging with the TWTA on, with battery pressures 634 psi and 19 psi, and main bus voltage at 24.9v. As the uplink was good, the mission operations team began loading uplink time consuming commands to EEPROM, i.e., autoexec macro 1 and bad gyro data parameter to EA and G&C. The S/C emergency was reinstated (had ended at midnight) and a 6.2 hour DSS-14 support was added starting at 1815z. As the signal had sufficient margin, the downlink rate was increased to 35 bps, which provides one (1 packet/frame) every 102 seconds. Eight good telemetry frames were received, including 3 memory dump packets and one temperature packet. Unnecessary systems that were found to be on were turned off to decrease the load on the battery. The 3 loads to EEPROM were verified from dumps received.


UPDATE:

Today, during 4 brief TWTA sampling periods this morning, communications are still continuous with the carrier signal fluctuating between -158 dBm and -164 dBm. The battery charge rate increased to C/4 for approximately 4 hours during the track this morning increasing the battery pressure by ~50 psi. An autonomous momentum dump parameter was loaded, dumped, and verified to EA RAM and EEPROM and G&C EEPROM. Detailed power subsystem telemetry was received and cell #6 and #9 (2 out of 11 cells) are indicating 0 volts. Propulsion tanks are slowly warming and have increased by ~2 deg C. IMU2 was powered on briefly and initial indications show that it is healthy and was used to confirm the estimated system momentum level (high). 54 telemetry packets were received. From the Doppler data analysis by the FDF, the nutation is slowing and returning to the previous spin axis orientation.

Progress continues on developing the plan and procedure to re-establish attitude control with very limited battery capacity by conducting an autonomous momentum dump in EA mode, powering on reaction wheels, and promoting the observatory to Standby mode.

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