ACE Weekly 04/30/04 - 05/06/04 All ACE spacecraft subsystems are performing nominally. No attitude maneuvers were executed this reporting period. The next attitude maneuver is scheduled for 05/12/04. ============================================================================ 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. - Installation of TAPS release 4.3 is tentatively scheduled for the first week of July 2004. All open DRs will be fixed in this release. ---------------------------------------------------------------------------- Automation (ROBOTT): - Release 0.6 installed on String 2 on 04/09/04. FOT testing is almost completed. -- 24 DRs have passed verification. 6 additional DRs have been opened as a result of FOT Testing. -- 1 DR (color allocation) still needs some work. There are no color issues if C&C is brought up by CRON or the Start Real-Time button. If C&C is brought up with the individual button, there still maybe some color issues, but these do not occur every day. - Installation of Release 0.6 to String 1 is planned for 05/13/05. Operations will be moved to String 2 prior to the installation. - SUG development is ongoing. A DRAFT version has been delivered and currently being reviewed by the FOT. - FOT training on ROBOTT began May 5th and additional sessions are being developed. ============================================================================ Extra Spacecraft Activities: None ===================================================================== Anomalies: DOY 04122 (05/01/04) ACE Anomaly G04-0033 - GDS 26m (DSS-16)- Exciter Problem DSS-16 reported having problems getting good lock with the spacecraft. A reset of the exciter corrected the problem. IMPACT: Delayed pass activities 10 minutes. All data recovered. DR# G104352 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~