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Full catalog/AST_09
AST_09·v004·dataset

Visible and infrared light from the surface (ASTER)

ASTER L2 Surface Radiance VNIR and SWIR V004
land NASA LPCLOUD Level 2 active COG
In plain English

What it measures. How much visible and infrared light the land surface reflects, after removing the haze and distortion the atmosphere adds. Visible/near-infrared comes at 15 m detail and shortwave-infrared at 30 m.

How it's made. Produced from the ASTER instrument on NASA's Terra satellite, by atmospherically correcting its Level-1B imagery into surface radiance.

How & where you'd use it. Used for detailed land and surface studies. Note the providers flag that ASTER's shortwave-infrared detectors stopped working in 2009 and that there was a 2024-25 data gap.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED FLUXSPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED IMAGERYSPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE FLUXSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE IMAGERYSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2000-03-06 → ongoing
  • Measured byTerra (ASTER)
  • Processing levelLevel 2
  • Spatial extent-180, -83, 180, 83
  • FormatsCOG
  • StatusACTIVE

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 Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Surface Radiance VNIR and SWIR (AST_09) contains atmospherically corrected data for the Visible and Near Infrared (VNIR) and Shortwave Infrared (SWIR) sensors. Both the VNIR and SWIR data are atmospherically corrected and are generated using the bands of the corresponding ASTER [Level 1B](https://doi.org/10.5067/ASTER/AST_L1B.004) image. The AST_09 product has a spatial resolution of 15 meters (m) for the VNIR bands and 30 m for the SWIR bands. Known Issues * Data acquisition gap: 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. Users should note the data gap in ASTER acquisitions from November 28, 2024, through January 16, 2025, for VNIR observations. * International date line: Level 2 products that are on the international date line/anti-meridian have incorrect bounding coordinates for the Universal Transverse Mercator (UTM) zone defined in the file metadata. * SWIR bands: ASTER SWIR detectors are no longer functioning as of January 12, 2009, due to anomalously high SWIR detector temperatures. * SWIR anomaly: Users are advised that ASTER SWIR data acquired from April 2008 to January 11, 2009, 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](https://lpdaac.usgs.gov/documents/1661/ASTER_SWIR_User_Advisory_Jan_12_2009.pdf) for more details.

Get the data

ast_09_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AST_09",
    version="004",
    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.