AST_L1A v003

ASTER L1A Reconstructed Unprocessed Instrument Data


PI: U.S./Japan ASTER Science Team

Description

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Level 1A (AST_L1A) contains reconstructed, instrument digital numbers (DNs) derived from the acquired telemetry streams of the telescopes: Visible and Near Infrared (VNIR), Shortwave Infrared (SWIR), and Thermal Infrared (TIR). Additionally, geometric correction coefficients and radiometric calibration coefficients are calculated and appended to the metadata, but not applied.

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Characteristics

Improvements/Changes from Previous Versions

  • Geometric correction to account for Earth’s rotation angle and nutation.
  • Geometric correction for geolocation errors associated with nighttime TIR scenes.
  • Radiometric correction to account for degradation of on-board calibration lamps.

Collection and Granule

Collection

Characteristic Description
CollectionTerra ASTER
DOI10.5067/ASTER/AST_L1A.003
File Size~90 MB
Temporal ResolutionOther
Temporal Extent2000-03-04 to Present
Spatial ExtentGlobal
Coordinate SystemN/A
DatumWorld Geodetic System (WGS84)
File FormatHDF-EOS
Geographic Dimensions~60 km x 60 km

Granule

Characteristic Description
Number of Science Dataset (SDS) Layers15
Columns/Rows4100 (VNIR), 5000 (VNIR 3B), 2048 (SWIR), and 700 (TIR) x 4200 (VNIR), 5400 (VNIR 3B), 2100 (SWIR), and 700 (TIR)
Pixel Size15 m (VNIR), 30 m (SWIR), and 90 m (TIR)

Layers

SDS Name Description Units Data Type Fill Value No Data Value Valid Range Scale Factor
VNIR_Band1 15 meter resolution VNIR Band 1 (0.52 to 0.60 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
VNIR_Band2 15 meter resolution VNIR Band 2 (0.63 to 0.69 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
VNIR_Band3N 15 meter resolution VNIR Band 3N (0.78 to 0.86 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
VNIR_Band3B 15 meter resolution VNIR Band 3B (0.78 to 0.86 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band4 30 meter resolution SWIR Band 4 (1.600 to 1.700 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band5 30 meter resolution SWIR Band 5 (2.145 to 2.185 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band6 30 meter resolution SWIR Band 6 (2.185 to 2.225 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band7 30 meter resolution SWIR Band 7 (2.235 to 2.285 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band8 30 meter resolution SWIR Band 8 (2.295 to 2.365 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
SWIR_Band9 30 meter resolution SWIR Band 9 (2.360 to 2.430 µm) N/A 8-bit unsigned integer N/A N/A 0 to 255 N/A
TIR_Band10 90 meter resolution TIR Band 10 (8.125 to 8.475 µm) N/A 16-bit unsigned integer N/A N/A 0 to 65535 N/A
TIR_Band11 90 meter resolution TIR Band 11 (8.475 to 8.825 µm) N/A 16-bit unsigned integer N/A N/A 0 to 65535 N/A
TIR_Band12 90 meter resolution TIR Band 12 (8.925 to 9.275 µm) N/A 16-bit unsigned integer N/A N/A 0 to 65535 N/A
TIR_Band13 90 meter resolution TIR Band 13 (10.25 to 10.95 µm) N/A 16-bit unsigned integer N/A N/A 0 to 65535 N/A
TIR_Band14 90 meter resolution TIR Band 14 (10.95 to 11.65 µm) N/A 16-bit unsigned integer N/A N/A 0 to 65535 N/A

Each HDF file contains multiple dimensions. See the User Guide for more information.

Known Issues

Users are advised that ASTER SWIR data acquired from April 2008 to the present exhibit anomalous saturation of values and anomalous striping. This effect is also present for some prior acquisition periods. Please refer to the ASTER SWIR User Advisory Document for more details.

Documentation

Using the Data

E-Learning

View from NASA Terra's Zoom Lens: All About the ASTER Sensor

Data In Action

Decline in Tea Quality Concerns Tea Growers

Highlights from the Literature: April to June 2017

Tools

Citation

DOI: 10.5067/ASTER/AST_L1A.003

About the Image

Terra ASTER reconstructed unprocessed instrument band combination 3n-2-1 data from the AST_L1A product over Guatemala on January 8, 2018.

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