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Full catalog/AST_L1A
AST_L1A·v003·dataset

Raw unprocessed instrument data (ASTER)

ASTER L1A Reconstructed Unprocessed Instrument Data V003
land NASA LPCLOUD Level 1A active HDF-EOS2
In plain English

What it measures. Raw, unprocessed instrument readings (digital numbers) from ASTER's three telescopes covering visible, shortwave infrared, and thermal infrared light, at resolutions from 15 m to 90 m. Calibration coefficients are included but not yet applied.

How it's made. Comes from the ASTER instrument on NASA's Terra satellite, reconstructed from the raw telemetry stream. Note: this version 3 product was retired in December 2025, with users pointed to version 4.

How & where you'd use it. A raw building-block input most people use via higher-level, calibrated ASTER products rather than directly. Users should also note known data quality issues and acquisition gaps.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › THERMAL INFRAREDSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE IMAGERY

Coverage & cadence

  • Time span2000-03-04 → ongoing
  • Measured byTerra (ASTER)
  • Processing levelLevel 1A
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusDEPRECATED

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The AST_L1A Version 3 data product was decommissioned on December 15, 2025. Users are encouraged to use the [AST_L1A Version 4 data product](https://doi.org/10.5067/ASTER/AST_L1A.004). 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. The AST_L1A product has a spatial resolution of 15 meters (m) for the VNIR bands, 30 m for the SWIR bands, and 90 m for the TIR bands. 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 for more details. * Data acquisition gaps: On November 28, 2024, one of Terra's power-transmitting shunt units failed. As a result, there was insufficient power to maintain functionality of the ASTER instrument. ASTER resumed acquisitions for the VNIR bands on January 18, 2025, and for the TIR bands on April 15, 2025. Users should note the data gap in ASTER acquisitions from November 28, 2024, through January 16, 2025, for VNIR observations, and a gap from November 28, 2024, through April 15, 2025, for TIR acquisitions. Processing Improvements/Changes * Starting June 23, 2021, radiometric calibration coefficient Version 5 (RCC V5) will be applied to newly observed ASTER data and archived ASTER data products. Details regarding RCC V5 are described in the following journal article. * Tsuchida, S., Yamamoto, H., Kouyama, T., Obata, K., Sakuma, F., Tachikawa, T., Kamei, A., Arai, K., Czapla-Myers, J.S., Biggar, S.F., and Thome, K.J., 2020, Radiometric Degradation Curves for the ASTER VNIR Processing Using Vicarious and Lunar Calibrations: Remote Sensing, v. 12, no. 3, at https://doi.org/10.3390/rs12030427.

Get the data

ast_l1a_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AST_L1A",
    version="003",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.