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Full catalog/AST_09XT
AST_09XT·v004·dataset

Light reflected off the land surface (ASTER)

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

What it measures. How much light the land surface reflects in visible, near-infrared, and shortwave-infrared wavelengths, after the blurring effect of the atmosphere has been removed.

How it's made. Produced from ASTER instrument imagery on the Terra satellite, with the visible/near-infrared bands at 15 m and shortwave bands at 30 m, atmospherically corrected from the raw Level 1B scenes.

How & where you'd use it. Used for mapping surface materials, vegetation, and geology. Note the shortwave bands stopped working in 2009, and there was a data gap in late 2024 to early 2025.

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 Crosstalk Corrected SWIR (AST_09XT) contains atmospherically corrected data for the Visible and Near Infrared (VNIR) and Shortwave Infrared (SWIR) sensors. The AST_09XT product has a spatial resolution of 15 meters (m) for the VNIR bands and 30 m for the SWIR bands. Both the VNIR and the SWIR data are atmospherically corrected using the corresponding bands from an ASTER [Level 1B](https://doi.org/10.5067/ASTER/AST_L1B.004) image. 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_09xt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AST_09XT",
    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.