ACE Weekly Report (04/19/02  04/25/02)

All ACE spacecraft subsystems are performing nominally.  The next
attitude maneuvers are scheduled for 04/26/02 and 05/06/02.

OCR CRIS-011 was executed on 04/25/02 to turn on the image intensifier
following recent solar activity.

An engineering test is in progress to determine a new HGA constraint.
The current constraint is 4.5 degrees.  The constraint will be increased
in several steps, over the next three months with the maximum constraint
being reached by late June, when the spacecraft will be at its maximum
range.  The first and largest step will be an increase to 5.5 degrees.
The approach used will be to allow the spacecraft to drift until the new
constraint would be violated.  An attitude maneuver would then be
executed.

Date:  HGA reached prior to Attitude Maneuver (degrees):
03/28/02    ~4.8
04/04/02    ~4.8
04/11/01    ~5.1
04/18/02    ~5.2
04/26/02    ~5.7(expected)

Analysis is ongoing, though no degradation in signal strength has been
seen.

Anomalies:
04/19/02  DOY 109 MOC experienced numerous vc2 hits for ~15 minutes
during D16 support.  Station and JPL notified of problem.  Problem
resolved shortly thereafter; all affected data was redumped during the
support (DR#N100383).