ACE Weekly 01/23/03 - 01/29/04

All ACE spacecraft subsystems are performing nominally. An attitude 
maneuver was successfully executed on 01/28/04. The next attitude maneuver 
is scheduled to occur on 02/06/04.

============================================================================
Orbit Events:

Per Craig Roberts (FDF):
The next ACE transit begins February 22 and ends March 15 (a span of 22.49 
days). This one will involve the closest angular approach to the Sun yet 
seen, i.e., 0.63 degree (deg) from solar center. (By comparison, the solar 
angular radius as seen from Earth at that epoch will be approx. 0.27 deg). 
The updated details and epochs (UTC) follow:

22 Feb      05:22      4.75 deg inbound
28 Feb      15:51      2.0 deg inbound
1 Mar       17:19      1.19 deg inbound
3 Mar       21:57      0.63 deg closest approach
6 Mar       13:40      1.19 deg outbound
8 Mar       17:55      2.0 deg outbound
15 Mar     16:14      4.75 deg outbound

The 1.19 deg reference was included because that was the closest approach 
during the December transit. ACE will spend 4.85 days within the 1.19 deg zone.

=====================================================================
OCRs Executed:

None.

=====================================================================
Ongoing Activities:

TAPS:
Release 4.1.13 was delivered on 01/06/04 and is currently being tested by 
the FOT. Open DRs have been prioritized by the FOT in preparation for 
transition.  The next two releases 4.2 and 4.2.1 are scheduled for 02/11/04 
and 03/03/04 respectively.  Upon delivery of Release 4.2, TAPS should 
contain all functionality required to allow for TAPS transition.

----------------------------------------------------------------------------
Automation (ROBOTT):
- Release 0.4 (HSM & OFFLINE) was installed on String 1 on 01/21/04. The 
Command & Control component was not delivered because it is NOT ready for 
operational use.
-  All DRs for Release 0.4 have been tested on String 1 and on 1/29/04 the 
FOT moved operations back to String 1.
-  FOT will begin testing next week on String 3 for C&C and the real-time 
monitor.

=====================================================================
Anomalies:

DOY 04027 (01/27/04) ACE Anomaly S04-0002 - Mnemonic STAR_BKGD Red High 
Limit Violation
The mnemonic STAR_BKGD ( Star Scanner Background High Flag) violated the 
Red High limit of 20, one time during the pass at 17:48:04.  The mnemonic 
came back within limits at 17:48:36.  IMPACT:  None.   The STAR_BKGD has 
been going over 20 (red high limit) for at least the past year.  But this 
is the first time we've observed 2 consecutive values out-of-limits during 
a pass.  STAR_BKGD is slowly increasing as one would expect after 6 years 
on-orbit.  The STAR_FA_CNT (Star Scanner False Alarm Count) is still less 
than 30.  No other problems have been found.  The FOT will continue to 
monitor the star scanner.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Glen A. Miller
ACE Flight Operations Observatory Engineer
Honeywell Technology Solutions Inc.
Goddard Space Flight Center
Building 14, Room W10A
Mail Stop 428.2
Greenbelt, MD 20771

Office: 301-286-7071
Pager: 800-425-3174
Fax:    301-286-1729
Email: gamiller@pop500.gsfc.nasa.gov
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~