ASTER - Advanced Spaceborne Thermal Emission and Reflection Radiometer
ASTER on Terra satellite
© Geoscience Australia
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a sensor onboard the Terra satellite (pictured right), launched in December 1999. The Terra satellite also carries the MODIS sensor and follows a similar orbit to Landsat 7. ASTER is the result of a cooperative effort between NASA and Japan's Ministry of Economy, Trade and Industry (METI) and the Japan Space Systems (formerly ERSDAC).
ASTER data may be used for a range of applications including land-use studies, mapping, geology, water resources, coastal resources, environment and generation of digital elevation models (DEM).
Satellite characteristics
ASTER's spectral bands and spatial resolution are generally more detailed than those of Landsat, meaning it is particularly useful for geological studies as well as environmental monitoring. However, unlike Landsat, repeat coverage by the ASTER sensor is more infrequent.
The ASTER instrument consists of three separate instrument subsystems:
- Visible and Near Infrared (VNIR)
- Shortwave Infrared (SWIR) - No longer functioning
- Thermal Infrared (TIR).
ASTER has 14 bands of information according to the following table:
| Instrument | VNIR | SWIR | TIR |
|---|---|---|---|
| Bands | 1-3 | 4-9 | 10-14 |
| Spatial resolution | 15m | 30m | 90m |
| Swath width | 60km | 60km | 60km |
| Cross track pointing | ± 318km (24 deg) | ±116km 8.55 deg) | ±116km (8.55 deg) |
| Quantisation (bits) | 8 | 8 | 12 |
| Note: Band 3 has nadir and backward telescopes for stereo pairs from a single orbit. | |||
The spectral range of each band is shown in the following diagram and table (courtesy NASA):
| Characteristic | VNIR | SWIR | TIR |
|---|---|---|---|
| Spectral Range | Band 1: 0.52 - 0.60 «m (visible green) Nadir looking | Band 4: 1.600 - 1.700 «m | Band 10: 8.125 - 8.475 «m |
| Band 2: 0.63 - 0.69 «m (visible red) Nadir looking | Band 5: 2.145 - 2.185 «m | Band 11: 8.475 - 8.825 «m | |
| Band 3: 0.76 - 0.86 «m (near infra-red) Nadir looking | Band 6: 2.185 - 2.225 «m | Band 12: 8.925 - 9.275 «m | |
| Band 3: 0.76 - 0.86 «m (near infra-red) Backward looking | Band 7: 2.235 - 2.285 «m | Band 13: 10.25 - 10.95 «m | |
| - | Band 8: 2.295 - 2.365 «m | Band 14: 10.95 - 11.65 «m | |
| - | Band 9: 2.360 - 2.430 «m | - |
Topic contact: earth.observation@ga.gov.au Last updated: February 21, 2013
