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Dear CSPP User Community. We received this information about the SNPP science data. There are currently significant geolocation errors.
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From NOAA Mission Operations

Overnight 7/9/2024, 2146 UTC the S-NPP GPS Receiver entered an invalid State. As a result S-NPP Science Data will slowly become invalid as its timestamp's drifts, primarily due to the timestamps being based off of only the internal spacecraft clock. NESDIS Mission Ops Engineering is planning to reset (power cycle) the S-NPP GPS, but no sooner than Friday 7/12/2024 due to other mission priorities.

Reminder that this satellite is tertiary to NOAA-21 and NOAA-20 and therefore recovery efforts are assessed, planned, and executed during business hours.

The data is now subject to significant geolocation errors. Some of you might still get data through Direct Readout capabilities, and so I wanted to provide a heads up that the data should be used with caution.

Official announcement from NOAA:

Product Anomaly: GPS invalid on S-NPP Spacecraft - Issued July 10, 2024 1638Z

Date/Time Issued: July 10, 2024 1638Z

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

Date/Time of Initial Impact: July 09, 2024 2146Z

Date/Time of Expected End Time: TBD

Length of Event: TBD

Details: Starting on July 09 at ~2146Z , the GPS receiver 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 July 12, 2024.

All PDA OPS subscriptions for all S-NPP science products will be disabled at 1630Z on July 10, 2024.

S-NPP direct broadcast (High Rate data (HRD)) will be disabled on July 10 at 1743Z for all science products.

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

Update #1 Issued July 16, 2024 18:23 UTC: The spacecraft recovery activities performed thus far on the S-NPP spacecraft did not resolve the degradation of the S-NPP science products seen following this anomaly. Engineering is working with the spacecraft vendor to develop a plan for a path forward.

S-NPP science data will remain disabled from PDA OPS and through direct broadcast until further notice.

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

Update #2: GPS invalid on S-NPP Spacecraft - Issued July 18, 2024 16:11 UTC.

Operations was able to recover the S-NPP spacecraft to a valid GPS timing and geolocation state on Jul 16. Cal/Val teams have confirmed that S-NPP Science products are meeting mission specifications and ready for operational use.

S-NPP Science products will be enabled on PDA OPS at 16:30 UTC on July 18, 2024. Science data after 16:30 UTC on July 18, 2024 will meet mission specifications.

Satellite direct broadcast (High Rate Data (HRD)) will be enabled at the end of rev #65934 at 17:03 UTC on July 18, 2024. Direct Broadcast (DB) users can use the equivalent S-NPP science Community Satellite Processing Package (CSPP) LEO products for operations.