ACE Weekly 03/26/04 - 04/01/04 All ACE spacecraft subsystems are performing nominally. No attitude maneuvers were executed this reporting period. The next attitude maneuver is tentatively scheduled for 04/02/04. ============================================================================ 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: None ===================================================================== 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): - Testing of Release 0.5 is progressing well. This release will not be placed on String 1. - Failover monitor/CRON testing began 03/19/04 with some minor problems identified. - ROBOTT Release 0.6 has a target date of 04/07/04. This release will not include any GTAS tasks and will include any fixed DRs at that time. - The color allocation problem with TPOCC has been corrected. ============================================================================ Extra Spacecraft Activities: - Submitted a draft OCR to M. Popecki for the S3DPU Anti-Reset Patch activity. All loads have been built and reviewed by both M. Popecki and the FOT. Uploading of the Anti-Reset patch will possibly occur within the next couple weeks pending completion of supporting OCRs for SEPICA, SWICS, and SWIMS and final NASA approval. - The window of opportunity to execute the patch will open when we have two or more active regions in the Eastern hemisphere of the Sun, with at least one near the central meridian. They should be producing X ray flares. ===================================================================== Anomalies: DOY 04092 (04/01/04) ACE Anomaly G04-0023 - MAD 26m DSS-66 - Resweep Required When carrier was brought up, DSS-66 was not able to get lock on the spacecraft's Receiver B. Instructed station to resweep and Receiver B subsequently was able to obtain LOCK. IMPACT: Delayed pass activities approximately 5 minutes. DR# M102401 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~