Aqua Daily Report May 10, 2002 1130 GMT - May 13, 2002 1130 GMT

Status Report From: Goddard Space Flight Center
Posted: Monday, May 13, 2002

The following activities were completed:

  1. Delta-V demonstration maneuvers. The activity was performed in two parts, the first with a zero duration burn (Friday, May 10 at 1514 GMT), the second with a 30-sec duration burn (Saturday, May 11 at 1724 GMT). Both events demonstrated the overall functionality of the Delta-V sequence, which includes:
    1. Load and Dump Delta-V Maneuver SCSs
    2. Open Isovalve
    3. Turn ON Cat Bed Heater
    4. Yaw Maneuver to Offset Attitude
    5. Burn
    6. Yaw Maneuver to Nominal Attitude
    7. Turn OFF Cat Bed Heaters
    8. Re-enable FPM Fault management
    9. Additionally, the 30-sec burn demonstrated thruster off-modulation functionality. Performance during both events was nominal.
  2. Uplinked the daily Master Command Loads and Ephemeris each day. On Friday (May 10), we uplinked the ephemeris with the continuity check enabled (our standard operating procedure). This was the first time since loading the continuity update patch (loaded Thursday, May 9) and the ephemeris loaded nominally.
  3. Activated the X-Band Communication Subsystem (Friday, May10). All indicators were nominal.
  4. First X-Band SSR Playback, containing State-of-Health Data (Friday, May10). The data was successfully downlinked to the EPGN site and routed to EDOS for processing. Performance was nominal and the data has been processed.
  5. Partitioned the SSR for Science Data, Routed the Science Data to the SSR only, and Enabled CERES Instrument Science Transactions (Saturday, May11). All events were nominal.
  6. First Dump of the SSR with Science Partitioning (Saturday, May11). The data was received and processed nominally.
  7. Powered on the AMSU-A1 and A2 instruments, performed a functional test on both instruments, and activated the AMSU telemetry monitors (TMONs). All activities completed nominally (Sunday, May12).
  8. Executed the AIRS warm functional checkout, Part 1 (Sunday, May12). Instrument performance was nominal. The instrument is now producing flexible packets, which are being successfully captured on the SSR and processed by the ground system.
  9. Began preparations for the first Ascent Delta-V maneuver (Monday, May13). Steps completed:
    1. Load and Dump Delta-V Maneuver SCSs
    2. Open Isovalve
    3. Turn ON Cat Bed Heater
    4. Yaw Maneuver to Offset Attitude

The following activities are scheduled for the next 24 hours:

  1. Execute the first Ascent Delta-V maneuver.
  2. Post-maneuver, return the AMSU-A instruments to full scan mode.
  3. Power on the HSB instrument, perform a functional test, and place the instrument in normal mode.

Aqua Spacecraft Status:

  1. Spacecraft State is currently Standby.
  2. GNC Mode is Fine 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 Parked at the warm calibration target for the maneuver.
  4. AMSU A2 is Parked at the warm calibration target for the maneuver.
  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. None.


  1. Nothing further to report on the apparent misalignment of approximately 0.2 degrees between Star Tracker Assembly (STA) 1 and STA2. The actions stated in the May 10 daily continue.
  2. There have been a total of 18 occurrences (5 since the May 10th daily) of the Command Telemetry Controller (CTC) receiving incomplete transfer frames from Transponder Interface Electronics (TIE) – (formerly CLCW errors not associated with commands). This anomaly has still not affected the ability to command the spacecraft and it has been safe at all times. The actions stated in the May 10 daily continue.
  3. A frequency command to USO-1P did not produce the expected frequency adjustment. A frequency adjust command to USO-2P did not have any apparent effect at all on USO-2P. The GIRD clock, controlled by USO-1P, is drifting at 27 ms/day. The GIIS clock, controlled by USO-2P, is drifting at 29 ms/day. There are two problems being investigated; frequency commanding of both USOs and correct addressing to USO-2P.
    1. The flight software refresh commanding of the USO is adversely affecting the serial interface between the CTC and the USO. The effect is limiting the ability to get any complete frequency commands across the interface. A flight software patch is being investigated to spread out the refresh commanding over several minor cycles.
    2. The PMDB has the frequency commands of USO-1R and USO-2P swapped. This has been verified by looking at the bit patterns. A temporary workaround is to use the USO-1R mnemonic to command USO-2P.

    // end //

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