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Full catalog/MOD021KM
MOD021KM·v6.1·dataset

Raw calibrated satellite imagery (Terra MODIS, 1 km)

MODIS/Terra Calibrated Radiances 5-Min L1B Swath 1km
land NASA LAADS Level 1B active HDF-EOS
In plain English

What it measures. Raw, calibrated satellite imagery from Terra's MODIS camera: how much light and infrared energy reached the sensor across 36 wavelength bands, from visible through thermal infrared, at about 1 km detail.

How it's made. Generated by converting MODIS's raw scans into standardized energy units, with location, quality flags, and error estimates added; visible bands are captured by day, thermal bands around the clock.

How & where you'd use it. A foundational input behind countless MODIS products (land, ocean, atmosphere); most people encounter it indirectly through those higher-level maps rather than using the raw radiances directly.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2000-02-24 → ongoing
  • Measured byTerra (MODIS)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS
  • 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 MODIS/Terra Calibrated Radiances 5Min L1B Swath 1km data set contains calibrated and geolocated at-aperture radiances for 36 discrete bands located in the 0.4 to 14.4 micron region of the electromagnetic spectrum. These data are generated from the MODIS Level 1A scans of raw radiance which during processing are converted to geophysical units of W/(m^2 um sr). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared, and near infrared measurements are only made during the daytime (except band 26), while radiances for the thermal infrared region (bands 20-25, 27-36) are measured continuously. The shortname for this product is MOD021KM and is stored in the Earth Observing System Hierarchical Data Format (HDF-EOS). A typical file size is approximately 110 MB (a day granule around 150MB and a night granule around 70 MB). In this new version (Collection 6.1) of MOD021KM, an advanced technique is introduced to mitigate the crosstalk contamination issue among the LWIR PV bands using data from lunar calibration events. The electronic crosstalk contamination issue in the Terra long-wave infrared photovoltaic (LWIR PV) bands (27 -30), has existed since the beginning of the mission but become more noticeable during later half of the mission. The electronic crosstalk is where signal from each of the detectors among the LWIR PV bands can leak to the other detectors, producing a false signal contribution. This contamination has had a noticeable effect on the MODIS science products since 2010 for band 27, and since 2012 for bands 28 and 29. Environmental information derived from MODIS L1B measurements will offer a comprehensive and unprecedented look at terrestrial, atmospheric, and ocean phenomenology for a wide and diverse community of users throughout the world. See the MODIS Characterization Support Team webpage for more C6 product information at: https://mcst.gsfc.nasa.gov/l1b/product-information or visit the Science Team homepage at: https://modis.gsfc.nasa.gov/data/dataprod/

Get the data

mod021km_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD021KM",
    version="6.1",
    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 LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.