ASTER L2 Surface Emissivity V004

The Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Surface Emissivity (AST_05) is produced using the Temperature/Emissivity Separation (TES) algorithm for the five Thermal Infrared (TIR) 90 meter bands, acquired during the day or night. The product comprises per-pixel emissivity measurements generated over land in addition to embedded metadata and quality assurance data planes. Acquisitions for AST_05 ended on January 16, 2026, at 05:10:45 UTC, when the ASTER TIR instrument was permanently turned off due to power limitations on the Terra spacecraft. More information is available in this [NASA Science News Brief](https://science.nasa.gov/blogs/science-news/2026/02/12/terra-adjusts-instrument-operations-to-extend-mission-life/). Known Issues * Level 2 products that are on the international date line/anti-meridian have incorrect bounding coordinates for the Universal Transverse Mercator (UTM) zone defined in the file metadata.