HUBBLE SPACE TELESCOPE

       DAILY REPORT #2518

PERIOD COVERED:  0000Z (UTC) 12/10/99 - 0000Z (UTC) 12/13/99

Daily Status Report as of 347/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

Since HST remains in Zero Gyro Sun Point (ZGSP), no science observations 
were performed.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:

                                         No activity

    2.2 FHST Updates:

                                         No activity

    2.3 Operations Notes:

        The HST continues in ZGSP.

        Operations Note #661 was used three times to reset the time-based 
recharge ratio charge/discharge buffer.

        The NSSC-1 status buffer was dumped at 344/2324Z per ROP NS-3.

        As described in HSTAR 7399, the DIU Serial Test Code (DDIUREQS) 
flagged out-of-limits low ("STC failed") for one telemetry sample at 
345/105046Z.

        At 346/025904Z, the battery #5 temperature (CBAT5TMP) went 
out-of-limits high with a value of 2.11 degrees C for 31 seconds.  This 
anomalous condition occurred about 10 minutes and the HST entered orbit 
day.  Over the course of night, the parameter again flagged high with the 
same value, and then increased to a value of about 2.8 degrees C.  In 
addition the battery #5 recharge ratio also flagged high (1.26) at 
346/1259Z.  Batteries 1 through 4 recharge ratios appeared to to decreasing 
slightly.

        Per HSTAR 7401, the Actuator Control Electronics (ACE) Primary Bus 
Voltage (EACEPBUS) flagged out-of-limits high at 29.53 volts for one 7.5 
second sample and then returned to its nominal value of 0.01 volts.  The 
ACE was powered off at the time.  Bad data quality is assumed, although no 
source of bad data could be determined.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Servicing Mission 3A, currently scheduled for December 16, 1999.

/CAW