S-NPP GPS and data geolocation issue

The following notice has been issued by NOAA ESPC Operations. Many products using S-NPP have been suspended or degraded. Please use caution if using S-NPP data during this period of geolocation degradation.  Additional updates can be found on NOAA OSPO's

https://www.ospo.noaa.gov/Operations/messages.html

Update #2: Due to increased degradation seen in all S-NPP science products, all S-NPP science products will be disabled on PDA OPS at 16:00 UTC on May 30, 2024.

While S-NPP High Rate data (HRD) is enabled, Direct Broadcast (DB) users are advised that this S-NPP science data is not yet cleared for operational use. 

This science data will continue to be available through GRAVITE, CLASS and PDA I&T through which the Cal/Val teams and PALs can perform their full analysis.

The anticipated reset of the S-NPP GPS unit is now expected to be executed no earlier than June 3, 2024.

Update #1: PDA OPS subscription for all S-NPP OMPS Limb Profile (LP) Products including blended LTOAST products will be disabled at 21:00 UTC on May 29th, 2024.

Users are advised that these S-NPP LIMB products have been degraded since May 25th, 2024.

As S-NPP High Rate data (HRD) remains enabled for OMPS LP products, Direct Broadcast (DB) users are advised that this S-NPP OMPS LP science data is not yet cleared for operational use.

Topic: GPS invalid on S-NPP spacecraft 

Date/Time Issued: May 30, 2024  1610Z

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

Date/Time of Initial Impact: May 25, 2024 22:30 UTC

Date/Time of expected end Time:   TBD

Duration: TBD

Details: Starting on May 25 at ~22:30 UTC, the GPS on the S-NPP spacecraft toggled to invalid causing the geolocation of all observed data to be inaccurate and out of the mission specifications. Engineering has started planning the execution of the reset of the GPS unit on the S-NPP spacecraft. The anticipated reset of the GPS unit is expected no earlier than May 29, 2024. All PDA OPS subscriptions for all S-NPP VIIRS science products will be disabled at 17:00 UTC on May 28, 2024. 

As S-NPP High Rate data (HRD) remains enabled for all VIIRS products, Direct Broadcast (DB) users are advised that this S-NPP VIIRS science data is not yet cleared for operational use.

The NOAA-21 and NOAA-20 satellites will continue to provide JPSS VIIRS science data as the primary and secondary satellites, respectively.