On November 28, 2024, at 14:20 UTC, one of Terra's power-transmitting shunt units failed. As a result, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument was put into safe mode. The Terra Flight Operations Team (FOT) resumed imaging with ASTER’s Visible and Near Infrared (VNIR) instrument on January 17, 2025.
On February 1, 2025, the Terra Measurement of Pollution in the Troposphere (MOPITT) instrument was put into safe mode. The FOT has continued monitoring power usage, and on April 15, 2025, ASTER’s Thermal Infrared (TIR) instrument resumed operations and began collecting data.
Users should note the data gap in ASTER acquisitions from November 28, 2024, through January 16, 2025, for VNIR observations, and a gap from November 28, 2024, through April 15, 2025, for TIR acquisitions.
Please see below for a list of available products containing ASTER TIR data:
- ASTER Level 1A Reconstructed Unprocessed Instrument Data (AST_L1A)
- ASTER Level 1B Registered Radiance at the Sensor (AST_L1B)
- ASTER Level 1 Precision Terrain Corrected Registered At-Sensor Radiance (AST_L1T v3 and v3.1)
- ASTER L2 Surface Emissivity (AST_05)
- ASTER L2 Surface Kinetic Temperature (AST_08)
- ASTER L2 Surface Radiance TIR (AST_09T)
- ASTER Digital Elevation Model and Orthorectified Registered Radiance at the Sensor (AST14DMO)
- ASTER Orthorectified Registered Radiance at the Sensor (AST14OTH)
ASTER data can be accessed using NASA’s Earthdata Search.
Thank you for your patience during the recent safe mode event. We offer our sincerest apologies for any inconvenience this may have caused.
Please contact the Land Processes Distributed Active Archive Center (LP DAAC) User Services with any questions.