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 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~