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Full catalog/AST_05
AST_05·v004·dataset

How well the surface radiates heat (ASTER)

ASTER L2 Surface Emissivity V004
land NASA LPCLOUD Level 2 COG
In plain English

What it measures. How efficiently the land surface radiates heat, measured for five thermal channels at 90 m resolution. This 'emissivity' depends on what the surface is made of, such as rock, sand, or vegetation.

How it's made. Produced from the ASTER instrument on the Terra satellite by separating surface temperature from emissivity in its thermal-infrared bands; the instrument was permanently switched off in January 2026.

How & where you'd use it. Useful for mapping rock and mineral types, studying soils and bare ground, and correcting other heat-based measurements of the land.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › EMISSIVITY

Coverage & cadence

  • Time span2000-03-04 → 2026-01-16
  • Measured byTerra (ASTER)
  • Processing levelLevel 2
  • Spatial extent-180, -83, 180, 83
  • FormatsCOG
  • StatusCOMPLETE

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 Emissivity (AST_05) is produced using the Temperature/Emissivity Separation (TES) algorithm for the five Thermal Infrared (TIR) 90 meter bands, acquired during the day or night. The product comprises per-pixel emissivity measurements generated over land in addition to embedded metadata and quality assurance data planes. Acquisitions for AST_05 ended on January 16, 2026, at 05:10:45 UTC, when the ASTER TIR instrument was permanently turned off due to power limitations on the Terra spacecraft. More information is available in this [NASA Science News Brief](https://science.nasa.gov/blogs/science-news/2026/02/12/terra-adjusts-instrument-operations-to-extend-mission-life/). Known Issues * 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.

Get the data

ast_05_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AST_05",
    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.