Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) shortwave infrared (SWIR) detectors are no longer functioning due to anomalously high SWIR detector temperatures. ASTER SWIR data acquired since April 2008 are not useable, and show saturation of values and severe striping; please refer to the table below. All attempts to bring the SWIR bands back to life have failed, and no further action is envisioned. Visible near-infrared (VNIR) and thermal infrared (TIR) data continue to show excellent quality, meeting all mission requirements and specifications.
NASA's Land Processes Distributed Active Archive Center (LP DAAC) offers nearly 1.5 million global ASTER Level 1A scenes and related on-demand products. The vast majority of these scenes were acquired prior to the SWIR detector temperature increase, and SWIR bands present may be used in investigations.
No further alerts are anticipated regarding the SWIR detector temperature situation.
LP DAAC Product Impacts Due to ASTER SWIR Anomaly
Shortname * indicates impacted, primarily commencing April 23, 2008 | Product | SWIR Bands 4-9 Normally Included? | SWIR Anomaly Impact to Product * indicates primarily commencing April 23, 2008 |
|---|---|---|---|
| *AST_1A | Reconstructed Unprocessed Instrument Data | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still usable. |
| *AST_1AE | Expedited Reconstructed Unprocessed Instrument Data | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still usable. |
| *AST_L1B | Expedited Registered Radiance at the Sensor | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still usable. |
| *AST_L1BE | Registered Radiance at the Sensor | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still usable. |
| AST_04 | Brightness Temperature at the Sensor | No | No impact. Only require TIR bands 10-14. |
| AST_05 | Surface Emissivity | No | No impact. Only require TIR bands 10-14. |
| *AST_06SD | Decorrelation Stretch SWIR | Yes | *Product unusable. |
| AST_06TD | Decorrelation Stretch TIR | No | No impact. Only require TIR bands 10-14. |
| AST_06VD | Decorrelation Stretch VNIR | No | No impact. Only require VNIR bands 1-3. |
| *AST_07 | Surface Reflectance (multi-file VNIR & SWIR) | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 still useable. |
| *AST_07XT | Surface Reflectance Crosstalk-Corrected (multi-file VNIR & SWIR) | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 still useable. |
| AST_08 | Surface Kinetic Temperature | No | No impact, only require TIR bands 10-14. |
| *AST_09 | Surface Radiance (multi-file VNIR & SWIR) | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 still usable. |
| AST_09T | Surface Radiance TIR | No | No impact, only require TIR bands 10-14. |
| *AST09XT | Surface Radiance Crosstalk-Corrected (multi-file VNIR & SWIR) | Yes | *SWIR 4-9 unusable. VNIR bands 1-3 still usable. |
| *AST13POL | Polar Surface and Cloud Classification | Yes | *Product unusable. |
| AST14DEM | Relative Digital Elevation Model | No | No impact, only require VNIR bands 3N and 3B. |
| *AST140TH | Orthorectified Images | Yes | *SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still useable. |
| *AST14DM0 | DEM and Orthorectified Images | Yes | *Ortho impact: SWIR bands 4-9 unusable. VNIR bands 1-3 and TIR bands 10-14 still usable. No DEM impact. |