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The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is the only high spatial resolution instrument aboard the Terra satellite, capturing images of Earth in 14 different wavelengths of the electromagnetic spectrum, from visible to thermal infrared light. 

ASTER data are used to generate the Global Digital Elevation Model (GDEM), which provides near-global coverage of Earth's land surface at approximately 30-meter spatial resolution. ASTER GDEM is available for download through NASA’s Earthdata Search.

ASTER Filenames

ASTER filenames (i.e., the local granule ID) follow a naming convention which provides useful information regarding the specific product.

In this example, the filename AST_L1T_00309122019230211_20190913112425_15725 indicates:

  • AST_L1T – Product Short Name
  • 004 – Collection Version
  • 09122019 – Calendar Date of Acquisition (MMDDYYYY)
  • 230211 – Hours, Minutes, and Seconds of Acquisition (HHMMSS)
  • 20190913 – Calendar Date of Processing (YYYYMMDD)
  • 112425 – Hours, Minutes, and Seconds of Processing (HHMMSS)

ASTER Product Long Name

The ASTER Product Long Name (i.e. Collection-Level) convention provides useful information regarding the product.

In this example, ASTER L1B Registered Radiance at the Sensor V004:

  • ASTER: Instrument/Sensor
  • L1B: Processing Level
  • Registered Radiance at the Sensor: Geophysical Parameter
  • V004: Collection or Version

LP DAAC distributes ASTER land data processed to Level 1 through 3:

  • Level-1A: Reconstructed, unprocessed instrument data at full resolution, time-referenced and annotated with ancillary information. Radiometric and geometric calibration coefficients and georeferencing parameters are included but not applied.
  • Level-1B: Level-1A data that have been radiometrically calibrated to at-sensor radiance and geometrically registered.
  • Level-2: Derived geophysical variables at the same resolution and location as Level-1 source data (swath products).
  • Level-3: Variables mapped to uniform spatial and/or temporal grid scales, typically resampled or composited to improve completeness, consistency, and ease of analysis.

The ASTER products have two primary sources of metadata: the embedded Hierarchical Data Format (HDF) metadata and the external Earth Observing System Data and Information System (EOSDIS) metadata, also known as the EOSDIS Core System (ECS) metadata. The ECS metadata is provided as a separate metadata file in XML format for products that include external metadata.

For products distributed in HDF format, georeferencing information should be obtained from the embedded HDF metadata. For products distributed as Cloud Optimized GeoTIFFs (COGs), georeferencing information is stored within the GeoTIFF structure. Other product-specific and core metadata may be referenced from the available metadata sources, depending on the product format and distribution.

Refer to the ASTER User Handbook for Level 1 products and the User Guide for higher-level products for detailed descriptions of individual core and product metadata attributes.

Learn more about ASTER

Specifications

Resolution

Spatial
  • VNIR (Visible and Near-Infrared) Bands 1, 2, 3N, 3B: 15 meter
  • SWIR (Shortwave Infrared) Bands 4–9: 30 meter
  • TIR (Thermal Infrared) Bands 10–14: 90 meter

Band 3 nadir (3N) and band 3 backward-looking (3B) allows capability of creating a Digital Elevation Model when both bands are acquired.

Spectral
  • VNIR: 0.52 - 0.86 µm
  • SWIR: 1.600 - 2.430 µm
  • TIR: 8.125 - 11.65 µm

More information on ASTER Spectral Bands

Temporal

Varies

Platforms

Terra

Launch Date
December 18, 1999
Altitude
705 km
Inclination
98.5°

Related Data Centers/Projects

LP DAAC

NASA's Land Processes Distributed Active Archive Center provides data crucial to the investigation, characterization, and monitoring of biological, geological, hydrological, ecological, and related conditions and processes.

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