Product/OUTAGE Anomaly,NOAA-18,All Instruments, MHS Spin State and Spacecraft Attitude Anomaly, 7 June 2009-Issued: 8 June 2009, 1520 UTC

MHS Spin State and Spacecraft Attitude Anomaly

Date/Time(UTC) Message Issued:
8 June 2009, 1520 UTC

Satellite(s) Involved:

Instrument(s) Involved:
MHS - Major impact
All instruments - Minor impact

Product(s) Involved/Affected:
MHS missing data
All Instrument/geolocation error increase

Date/Time(UTC) of Initial Implementation:
7 June 2009, Time 1847 UTC

Details/Specifics of Change
SOCC reported the following anomaly on NOAA-18:
At 2000 UTC of 7 June 2009, on rev 20863 contact at the Wallops CDA station, the MHS was detected in MOTOR SPIN STATE. The instrument was successfully recovered prior to Loss of Signal on rev 20863 at Wallops. The anomaly apparently began around 1847 UTC resulting in the loss of MHS data until the instrument was commanded back to scan mode around 2000 UTC.

Impacted passes:

At the same time the spacecraft attitude control mode switched from nominal to YGC attitude control mode where it remains currently. The user will see a slight increase in the geolocation error due to this change. Engineers are evaluating the event and the switch back to nominal attitude control mode will be made as soon as possible.

Contact Person(s) Name/Email/Phone Number for Questions:
Emily Harrod 301-817-3882 ESPC Level 1B operations support
Renee Smith Dearing 301-817-4117 SOCC Operations
Operations Control Leader 301-817-3880 ESPC Helpdesk support

Web site(s) that contain other relevant information (where applicable): - History of level 1B notices - All user notices - SOCC polar satellite status