Landsat 8 Safehold

Lurker · January 10, 2020

January 3, 2020 - Recent Landsat 8 Safehold Update
On December 19, 2019 at approximately 12:23 UTC, Landsat 8 experienced a spacecraft constraint which triggered entry into a Safehold. The Landsat 8 Flight Operations Team recovered the satellite from the event on December 20, 2019 (DOY 354). The spacecraft resumed nominal on-orbit operations and ground station processing on December 22, 2019 (DOY 356).

Data acquired between December 22, 2019 (DOY 356) and December 31, 2019 (DOY 365) exhibit some increased radiometric striping and minor geometric distortions (see image below) in addition to the normal Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) alignment offset apparent in Real-Time tier data. Acquisitions after December 31, 2019 (DOY 365) are consistent with pre-Safehold Real-Time tier data and are suitable for remote sensing use where applicable. All acquisitions after December 22, 2019 (DOY 356) will be reprocessed to meet typical Landsat data quality standards after the next TIRS Scene Select Mirror (SSM) calibration event, scheduled for January 11, 2020.

Landsat 8 Operational Land Imager acquisition on December 22, 2019 (path 148/row 044) after the spacecraft resumed nominal on-orbit operations and ground station processing. This acquisition demonstrates increased radiometric striping and minor geometric distortions observed in all data acquired between December 22, 2019 and December 31, 2019. All acquisitions after December 22, 2019 will be reprocessed on January 11, 2020 to achieve typical Landsat data quality standards.

Data not acquired during the Safehold event are listed below and displayed in purple on the map (click to enlarge).

Map displaying Landsat 8 scenes not acquired from Dec 19-22, 2019
Path 207 Rows 160-161
Path 223 Rows 60-178
Path 6 Rows 22-122
Path 22 Rows 18-122
Path 38 Rows 18-122
Path 54 Rows 18-214
Path 70 Rows 18-120
Path 86 Rows 24-110
Path 102 Rows 19-122
Path 118 Rows 18-185
Path 134 Rows 18-133
Path 150 Rows 18-133
Path 166 Rows 18-222
Path 182 Rows 18-131
Path 198 Rows 18-122
Path 214 Rows 34-122
Path 230 Rows 54-179
Path 13 Rows 18-122
Path 29 Rows 20-232
Path 45 Rows 18-133
After recovering from the Safehold successfully, data acquired on December 20, 2019 (DOY 354) and from most of the day on December 21, 2019 (DOY 355) were ingested into the USGS Landsat Archive and marked as "Engineering". These data are still being assessed to determine if they will be made available for download to users through all USGS Landsat data portals.