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Full catalog/AST_07XT
AST_07XT·v004·dataset

True surface color, crosstalk-corrected (ASTER)

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

What it measures. How much sunlight the Earth's surface reflects back to the sensor across visible, near-infrared, and shortwave-infrared light, corrected for atmospheric haze and viewing angle. Detail is 15 meters for the visible/near-infrared bands and 30 meters for the shortwave bands.

How it's made. Derived from ASTER imagery aboard NASA's Terra satellite by atmospherically correcting the raw measurements and removing a sensor artifact called crosstalk in the shortwave bands.

How & where you'd use it. Used for detailed land-surface and geology studies and mapping surface materials; note that the shortwave detectors stopped working in 2009, so newer data lacks those bands.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › ALBEDOLAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-03-06 → ongoing
  • Measured byTerra (ASTER)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • 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 Reflectance VNIR and Crosstalk Corrected SWIR (AST_07XT) dataset contains measures of the fraction of incoming solar radiation reflected from the Earth’s surface to the ASTER instrument corrected for atmospheric effects and viewing geometry for both 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 [L1B](https://doi.org/10.5067/ASTER/AST_L1B.004) image. The AST_07XT 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_07xt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AST_07XT",
    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.