Topic: S-NPP will execute a Risk Mitigation Maneuver (RMM) on October 28, 2018

Date/Time Issued: October 28, 2018 1640Z

Product(s) or Data Impacted: All S-NPP Sensor Data

Date/Time of Initial Impact: October 28, 2018 18:46:00Z

Date/Time of Expected End: October 29, 2018 04:32:00Z

Length of Outage: See Details.

Details/Specifics of Change: On October 28, 2018 at 19:12:00Z, S-NPP will perform a 0.3 second propulsive Risk Mitigation Maneuver (RMM) to due avoid a close approach with orbital debris. In the event we are unable to execute the primary burn at 19:12:00Z, a secondary burn opportunity has also been scheduled a two orbits later at at 22:40:00 Z. This maneuver will occur in daylight, a few minutes after spacecraft comes out of eclipse.

The following observatory systems will be affected on October 28, 2018 and October 29, 2018:

October 28 16:40:00Z - October 29 04:32:00 Z Some of ATMS Scan Reversal will be skipped.
Primary: 18:46:00z - 20:53:04z, or if needed Backup: 22:14:00z - 00:53:04z CERES in Contam-Safe mode, science data will not be available
Primary: 18:56:00z - 19:23:06z, or if needed Backup: 22:14:00z - 22:51:06z OMPS in Decon mode, Science data will not be available
Primary: 19:01:00z - 19:24:05z, or if needed Backup: 22:14:00z - 00:53:04z HRD will be off, data for direct broadcast users will be unavailable
Primary thruster firing: 19:12:00z, or if needed Backup: 22:40:00z S-NPP will remain in Mission Point, however, there may be thruster firing induced attitude errors for a few minutes after thruster firing. Any collected data during that time period may be impacted and not disseminated.