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Aqua Daily Report May 8, 2002 1130 GMT - May 9, 2002 1130 GMT

Status Report From: Goddard Space Flight Center
Posted: Thursday, May 9, 2002

The following activities were completed:

  1. The Master Command Load (MCL) for day 129 was loaded at 2010z and activated at 0000z.
  2. The daily spacecraft ephemeris table was loaded at 2140z.
  3. In preparation for Fine Point Mode (FPM) transition:
    1. Completed activation of Star Trackers
    2. Patch loaded to update the Loss of NADIR values at 1106z
    3. Uplinked Attitude Quaternion at 1359z.
    4. Initialized Star identification at 1400z.
    5. Enabled Attitude Propagation with the IRU at 2222z.
    6. Commanded the Solar Array Drive Assembly (SADA) to ephemeris mode at 0249z
    7. Enabled Hi Fi ephemeris propagation at 0250z.
    8. Developed updated Star Tracker alignment matrices in preparation for entering FPM, matrices uplinked at 0308z.
    9. Ephemeris continuity check patch was uplinked at 0314z.
  4. Completed loading AIRS ISC tables at 128/1102z.
  5. The Flight Software patch to aid in CLCW error troubleshooting was loaded and activated at 1752z.
  6. Performed S-Band Antenna Polarization Tests for EPGN at 1831z and for TDRS at 1938z.
  7. Transitioned AIRS to Standby with the Cooler Off at 1955z.

The following activities are scheduled for the next 24 hours:

  1. Uplink and activate the Master Command Load (MCL) for day 130.
  2. Uplink daily spacecraft ephemeris with continuity check.
  3. Uplink the FMU/SSR Reconfiguration SCSs.
  4. In preparation for Fine Point Mode (FPM) transition:
    1. Activation of Star Trackers.
    2. Uplink Attitude Quaternion.
    3. Initialize Star identification.
    4. Enable Attitude Propagation with the IRU.

Aqua Spacecraft Status:

  1. Spacecraft State is currently Standby.
  2. GNC Mode is Earth Point Mode, HiFi Ephemeris.

Aqua Instrument Status:

  1. AIRS is in Decontaminate state, Quiet bus is ON, Noisy bus is ON, Cryocooler is OFF, Scan mirror rotating is OFF and earth shield is CLOSED.
  2. AMSR-E is in Modified Sleep mode, rotating at 4 RPM.
  3. AMSU A1 is in Survival mode and the antenna is in the TARGET position.
  4. AMSU A2 is in Survival mode and the antenna is in the TARGET position.
  5. CERES Aft is in Safe mode and the covers are CLOSED.
  6. CERES Fore is in Safe mode and the covers are CLOSED.
  7. HSB is in Survival mode and the antenna is in the TARGET position.
  8. MODIS is in Standby mode, Nadir Door is Unlatched and CLOSED, Solar Diffuser Door is Unlatched and CLOSED, and the Space View Door is Unlatched and CLOSED.

Activities Deferred:

  1. Spacecraft transition to Fine Point Mode (FPM), which was delayed, will be performed today.
    1. Delta-V demonstration Yaw Maneuver is also delayed as a result.
    2. Other activation activities dependent on FPM are also delayed.
    3. After transition to FPM, remaining activation activities will be rescheduled.

Anomalies:

  1. Apparent shift (difference with pre-flight prediction) in alignment between the 2 Star Tracker Assemblies (STA’s).
    1. Flight dynamics analysis indicates potential change of 0.2 degrees in alignment between the two star trackers.
    2. Star identification was performed and the approximate 0.2 degrees misalignment was confirmed.
    3. Updated alignment matrices were uplinked in preparation for transition to FPM.
    4. Investigation ongoing to determine if this is a physical misalignment or transformation matrix error.
  2. Code word error interrupted AIRS table uploads on May 6 and 7, and was present when a dropped command occurred during MODIS power on May 7.
    1. Loads resent successfully.
    2. Code word errors not associated with uplink commands have also been observed on several other occasions.
    3. Delogs of telemetry and format table patches are underway to determine root cause.
    4. Spacecraft health and safety were never in danger at any time.
    5. Activation continues nominally.
  3. The ground system has experienced what appeared to be 2 anomalous passes at SGS, one occurred on May 6, and the second on May 7, where data were missing in the S-Band playbacks.
    1. No SSR data were actually lost because the data were replayed in subsequent passes.
    2. EOC Mission Operations Systems (EMOS) personnel and CSOC personnel have concluded that the actual playback data are good, and only idle frames at the beginning of the pass are affected. The FOT did not anticipate the affects of the low power levels of the RF signal at the horizon (manifested as Reed-Solomon corrupted CADUs) because all pre-launch testing was done with the RF signal at a constant power level. The phenomenon is seen only at the Norway stations because of the Norwegian antennas’ position on the plateau, they can see the true horizon (zero degrees elevation). The stations are operating within normal parameters.

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