ACE Weekly 04/09/04 - 04/15/04

All ACE spacecraft subsystems are performing nominally. An attitude 
maneuver was successfully executed on 04/14/04. The next attitude maneuver 
is tentatively scheduled for 04/27/04.

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

 From Craig Roberts (FDF):

The next ACE transit of the old Solar Exclusion Zone (SEZ) will run from 
05/19/04 to 06/14/04. For the first time ever, ACE will transit the solar 
disk on 06/01/04. On that date, the Sun's angular radius is 0.2629 degree 
(as seen from Earth's center). The solar transit will last nearly 21 hours 
(again, as seen from Earth's center). The main features of this transit are 
given in the following table (times are UTC).

5/19 01:42 4.75 deg inbound
5/27 07:45 2.0 deg inbound
5/30 23:39 0.63 deg inbound
6/01 01:18 0.2629 deg (kissing solar disk inbound)
6/01 10:46 0.197 deg (radius of closest approach to solar center)
6/01 22:14 0.2629 deg (kissing solar disk outbound)
6/02 23:28 0.63 deg outbound
6/06 11:15 2.0 deg outbound
6/14 07:18 4.75 deg outbound

The 0.63 deg epochs are included because that radius represents the closest 
approach during our last transit in February/March. ACE will spend almost 
exactly 3 days within this zone.

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

04/09/04 - SEP-104 (S3DPU Anti-Reset Patch v5C Upload and SEPICA 
Engineering Mode) Steps 1-6

04/09/04 - SWX-030 (SWICS Safing and Restoration) Step A, and SWX-031 
(SWIMS Safing and Restoration) Step A executed in support of SEP-104.

04/15/04 - SEP-106 (Increase the SEPICA Y and Z Thresholds)

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

TAPS:
- Transition from GTAS to TAPS occurred on 03/18/04. All trending 
activities are being accomplished using TAPS. No problems have been noted 
to date.

----------------------------------------------------------------------------
Automation (ROBOTT):
- Release 0.6 installed on String 2 on 04/09/04.  FOT testing of fixed DRs 
is ongoing, 10 DRs tested with 9 verified fixed to date.
- Installation of the latest release to String 1 is tentatively planned for 
the week of May 3rd.  The date is highly dependent on the FOT's testing 
progress.
- SUG development is ongoing.  Tentative release date is the end of May.  A 
DRAFT version may be available prior to that.

============================================================================
Extra Spacecraft Activities:

- Executed the S3DPU Anti-Reset Patch activity with Mark Popecki (SEPICA) 
and Scott Lasley (SWICS/SWIMS) monitoring. The S3DPU patch loads were 
successfully uploaded after SWICS and SWIMS were placed in STANDBY.  To 
date there have been no problems encountered with the new patch.  Mark 
Popecki continues to monitor S3DPU activity.  SWICS and SWIMS should return 
to NORMAL operations around 04/23/04.

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

NONE

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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
gamiller@pop500.gsfc.nasa.gov
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~